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+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 1: INTERFERENCE"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.10: Calculation_of_Wavelength_of_light.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"d = 0.0001 // distance between two slits in meter\n",
+"Beta = 0.005 // width of the fringes formed in meter\n",
+"D = 1 // distance between slit and screen in meter\n",
+"// Sample Problem 10 on page no. 1.43\n",
+"printf('\n # PROBLEM 10 # \n')\n",
+"lambda = (Beta * d) / D // calculation for wavelength of light = %e meter\n",
+"printf('\n Standard formula used \n lambda = (Beta * d) / D.\n')\n",
+"printf('\n Wavelength of light = %f A. ',lambda*1e10)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.11: Calculation_of_Fringe_width.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"alpha = %pi / 180 // angle of bi prism in radian\n",
+"mu = 1.5 // refractive index of biprism \n",
+"a = 0.4 // distance of bi prism from slit in meter\n",
+"b = 0.6 // distance of bi prism from screen in meter\n",
+"lambda = 5.893e-7 // wavelength of light in meter\n",
+"// Sample Problem 11 on page no. 1.43\n",
+"printf('\n # PROBLEM 11 # \n')\n",
+"D = a + b // calculation for distance between slits and screen\n",
+"fringe_width = (lambda * D) / (2 * a * (mu - 1) * alpha) // calculation for fringe width\n",
+"printf('\n Standard formula used \nD = a + b.\n fringe_width = (lambda * D) / (2 * a * (mu - 1) * alpha).\n ')\n",
+"printf('\n Fringe width = %e meter.',fringe_width)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.12: Calculation_of_Fringe_width.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"d1 = 4.05e-3 // distance between slits in first position in meter\n",
+"d2 = 2.90e-3 // distance between slits in second position in meter\n",
+"lambda = 5.893e-7 // wavelength of light in meter\n",
+"D = 1 // distance between slit and screen\n",
+"// Sample Problem 12 on page no. 1.44\n",
+"printf('\n # PROBLEM 12 # \n')\n",
+"d = sqrt(d1 * d2)// calculation for distance between fringe\n",
+"fringe_width = (lambda * D) / d // calculation for fringe width\n",
+"printf('\n Standard formula used \n d = sqrt(d1*d2),\n beta = lambda*D/d \n')\n",
+"printf('\n Fringe width = %f mm',fringe_width*1000)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.13: Calculation_of_Thickness_of_glass.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"fringe_width = 3.42e-4 // fringe width in meter\n",
+"mu = 1.542 // refractive index of glass\n",
+"Xn = 2.143e-3 // shift of central fringe in meter\n",
+"lambda = 5.89e-7 // wavelength of light in meter\n",
+"// Sample Problem 13 on page no. 1.44\n",
+"printf('\n # PROBLEM 13 # \n')\n",
+"n = Xn / fringe_width // calculation for order of the fringe\n",
+"t = (floor(n) * lambda) / (mu - 1) // calculation for thickness of the glass\n",
+"printf('\n Standard formula used \n (mu - 1)*t = n*lambda \n')\n",
+"printf('\n Thickness of glass sheet = %e meter. ',t)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.14: Calculation_of_Distance_between_coherent_sources.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"fringe_width = 9e-4 // fringe width in meter\n",
+"a = 0.1 // distance of bi prism from slit in meter\n",
+"b = 0.9 // distance of bi prism from screen in meter\n",
+"lambda = 5.896e-7 // wavelength of light in meter\n",
+"// Sample Problem 14 on page no. 1.45\n",
+"printf('\n # PROBLEM 14 # \n')\n",
+"D = a + b // calculation for distance between slits and screen\n",
+"d = (lambda * D) / fringe_width // calculation for distance between coherent sources\n",
+"printf('\n Standard formula used \n D = a + b. \n d = (lambda * D) / fringe_width.\n')\n",
+"printf('\n Distance between coherent sources = %e meter. ',d)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.15: Calculation_of_Wavelength_of_light.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"\n",
+"clc \n",
+"// Given that\n",
+"fringe_width = 1.35e-2 // fringe width in meter\n",
+"a = 0.5 // distance of bi prism from slits in meter\n",
+"b = 0.5 // distance of bi prism from screen in meter\n",
+"mu = 1.5 // refractive index of bi prism \n",
+"alpha = %pi / 360 // angle of bi prism in radian \n",
+"// Sample Problem 15 on page no. 1.45\n",
+"printf('\n # PROBLEM 15 # \n')\n",
+"D = a + b // calculation for distance between slits and screen \n",
+"lambda = (2 * a * (mu - 1) * alpha * fringe_width) / D // calculation for wavelength of light = %e meter\n",
+"printf('\n Standard formula used \n D = a + b. \nlambda = (2 * a * (mu - 1) * alpha * fringe_width) / D.\n ') \n",
+"printf('\n Wavelength of light = %f A. ',lambda*1e10)\n",
+"//Answer in the book:5893 A\n",
+"//Answer in the program:589048.622541 A\n",
+""
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.16: Calculation_of_Wavelength_of_light.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"a = 0.45 // distance between slit and bi prism in meter\n",
+"b = 0.45 // distance between screen and bi prism in meter\n",
+"alpha = %pi / 180 // angle of bi prism in radian\n",
+"Mu = 1.5 // refractive index of bi prism\n",
+"fringe_width = 1.56e-4 // fringe width in meter \n",
+"// Sample Problem 16 on page no. 1.45\n",
+"printf('\n # PROBLEM 16 # \n')\n",
+"D = a + b // calculation for distance between screen and slit\n",
+"lambda = (fringe_width * 2 * a * (Mu - 1) * alpha) / D // calculation for wavelength\n",
+"printf('\n Standard formula used \n lambda = (2a*(mu-1)*alpha*beta)/D. \n')\n",
+"printf('\n Wavelength of light = %f A.', lambda*1e10)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.17: Calculation_of_Wavelength_of_light.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"D = 1.20 // distance between source and eye piece in meter\n",
+"Xn = 1.9e-2 // distance move by eye piece for 20 fringe in meter\n",
+"n = 20 // no. of fringes\n",
+"d = 6e-4 // distance between slits in meter \n",
+"// Sample Problem 17 on page no. 1.45\n",
+"printf('\n # PROBLEM 17 # \n')\n",
+"lambda = (Xn * d) / (D * n)// calculation for wavelength\n",
+"printf('\n Standard formula used \n beta = lambda*D/d.')\n",
+"printf('\n Wavelength of light = %f A.', lambda*1e10)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.18: Calculation_of_No_of_fringes_observed_in_field_of_view_in_second_case.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"lambda1 = 5.890e-7 // wavelength of first light in meter\n",
+"lambda2 = 4.358e-7 // wavelength of second light in meter\n",
+"n1 = 40 // no. of fringes observed in the field of in first case \n",
+"// Sample Problem 18 on page no. 1.46\n",
+"printf('\n # PROBLEM 18 # \n')\n",
+"n2 = (n1 * lambda1) / lambda2 // by using formula n1*lambda1=n2*lambda2\n",
+"printf('\n Standard formula used \n n1*lambda1=n2*lambda2. \n')\n",
+"printf('\n No. of fringes observed in field of view in second case = %d. ', floor(n2))"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.19: Calculation_of_Least_thickness_of_soap_film.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"lambda = 5.893e-7 // wavelength of light in meter\n",
+"Mu = 1.42 // refractive index of soap film \n",
+"i = 0 // incidence angle in radian \n",
+"r = 0 // refracted angle in radian\n",
+"// Sample Problem 19 on page no. 1.46\n",
+"printf('\n # PROBLEM 19 # \n')\n",
+"n = 1 // for smallest thickness\n",
+"t1 = ((2 * n - 1) * lambda) / (4 * Mu * cos(r)) // calculation for east thickness of soap film for bright fringe\n",
+"t2 = (n * lambda) / (2 * Mu * cos(r)) // calculation for east thickness of soap film for dark fringe\n",
+"printf('\n Standard formula used \n thickness for bright fringe = ((2 * n - 1) * lambda) / (4 * Mu * cos(r)). \n thickness for dark fringe = (n * lambda) / (2 * Mu * cos(r)).\n ')\n",
+"printf('\n Least thickness of soap film -\n (a) For bright fringe = %e mm. \n (b) For dark fringe = %e mm.',t1*1000,t2*1000)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.1: Calculation_of_time_Coherence.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 6.6e-7 // wavelength of light in meter\n",
+"L = 1.32e-5 // coherence length in meter\n",
+"// Sample Problem 1 on page no. 1.40\n",
+"printf('\n # PROBLEM 1 # \n')\n",
+"printf('\n Standard formulae used \n delta_L = c * delta_t \n')\n",
+"coherence_time = L / (3 * 10 ^ 8)//calculation for coherence time\n",
+"printf('\n Coherence time = %e sec',coherence_time)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.20: Calculation_of_Thickness_of_oil_film.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"lambda = 5.89e-7 // wavelength of light in meter\n",
+"Mu_o = 1.4 // refractive index of oil film \n",
+"Mu_w = 1.33 // refractive index of water\n",
+"i = %pi / 6 // incidence angle in radian \n",
+"n = 6 // no. of fringes seen\n",
+"// Sample Problem 20 on page no. 1.46\n",
+"printf('\n # PROBLEM 20 # \n')\n",
+"r = asin(sin(i) / Mu_o) // calculation for angle of refraction\n",
+"t = (n * lambda) / (2 * Mu_o * cos(r)) // calculation for thickness of film\n",
+"printf('\n Standard formula used \n mu = sin(i)/sin(r),\n 1*mu*t*cos(r) = n*lambda. \n')\n",
+"printf('\n Thickness of oil film = %e mm.',t*1000)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.21: Calculation_of_Least_thickness_of_soap_film_for_bright_fringe.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"lambda = 6e-7 // wavelength of light in meter\n",
+"Mu = 1.463 // refractive index of soap film \n",
+"i = 0 // incidence angle in radian \n",
+"r = 0 // refracted angle in radian\n",
+"// Sample Problem 21 on page no. 1.47\n",
+"printf('\n # PROBLEM 21 # \n')\n",
+"n = 1 // for smallest thickness\n",
+"t = ((2 * n - 1) * lambda) / (4 * Mu * cos(r)) // calculation for least thickness of soap film for bright fringe\n",
+"printf('\n Standard formula used \n t = ((2 * n - 1) * lambda) / (4 * Mu * cos(r)).\n')\n",
+"printf('\n Least thickness of soap film for bright fringe = %e mm. ',t*1000)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.22: Calculation_of_Thickness_of_oil_film.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"lambda = 5.89e-7 // wavelength of light \n",
+"Mu_o = 1.46 // refractive index of oil film \n",
+"i = %pi / 6 // incidence angle in radian \n",
+"n = 8 // no. of fringe is seen\n",
+"// Sample Problem 22 on page no. 1.47\n",
+"printf('\n # PROBLEM 22 # \n')\n",
+"r = asin(sin(i) / Mu_o) // calculation for angle of refraction\n",
+"t = (n * lambda) / (2 * Mu_o * cos(r)) // calculation for thickness of oil film\n",
+"printf('\n Standard formula used \n r = asin(sin(i) / Mu_o.\n t = (n * lambda) / (2 * Mu_o * cos(r)).\n')\n",
+"printf('\n  Thickness of oil film = %e mm. ',t*1000)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.23: Calculation_of_No_of_dark_bands_seen_between_wavelengths.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"lambda1 = 4e-7 // max. wavelength of light in meter\n",
+"lambda2 = 5e-7 // min. wavelength of light in meter\n",
+"Mu = 1.4 // refractive index of soap film \n",
+"i = %pi / 4 // incidence angle in radian \n",
+"t = 1e-5 // thickness of oil film in meter\n",
+"// Sample Problem 23 on page no. 1.47\n",
+"printf('\n # PROBLEM 23 # \n')\n",
+"r = asin(sin(i) / Mu) // calculation for angle of refraction\n",
+"n1 = (2 * Mu * t * cos(r)) / lambda1 // calculation for no. of dark bands seen in the case of max. wavelength \n",
+"n2 = (2 * t * Mu * cos(r)) / lambda2 // calculation for no. of dark seen in the case of min. wavelength \n",
+"n = floor(n1) - floor(n2) // claculation for no. of dark bands seen between wavelengths\n",
+"printf('\n Standard formula used \n r = asin(sin(i) / Mu).\n n = (2 * Mu * t * cos(r)) / lambda.\n')\n",
+"printf('\n No. of dark bands seen between wavelengths. = %d',n)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.24: Calculation_of_Least_thickness_of_soap_film_for_bright_fringe.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"lambda = 5.89e-7 // wavelength of light in meter\n",
+"Mu = 1.5 // refractive index of soap film  \n",
+"r = %pi / 3 // refracted angle in radian\n",
+"// Sample Problem 24 on page no. 1.48\n",
+"printf('\n # PROBLEM 24 # \n')\n",
+"n = 1 // for smallest thickness\n",
+"t = (n * lambda) / (2 * Mu * cos(r)) // calculation for least thickness of soap film for bright fringe\n",
+"printf('\n Standard formula used \n t = (n * lambda) / (2 * Mu * cos(r)).\n')\n",
+"printf('\n Least thickness of soap film for bright fringe = %e meter. ',t)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.25: Calculation_of_Thickness_of_the_film.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"lambda1 = 6.1e-7 // max. wavelength of light in meter\n",
+"lambda2 = 6e-7 // min. wavelength of light in meter\n",
+"Mu = 1.333 // refractive index of  film \n",
+"i = %pi / 4 // incidence angle in radian \n",
+"// Sample Problem 25 on page no. 1.48\n",
+"printf('\n # PROBLEM 25 # \n')\n",
+"r = asin(sin(i) / Mu) // calculation for angle of refraction\n",
+"n = lambda2 / (lambda1 - lambda2) // calculation for no. of bright band\n",
+"t = (n * lambda1) / (2 * Mu * cos(r)) // calculation for thickness of the film\n",
+"printf('\n Standard formulae used \n r = asin(sin(i) / Mu).\n n = lambda2 / (lambda1 - lambda2).\n t = (n * lambda1) / (2 * Mu * cos(r)).\n')\n",
+"printf('\n Thickness of the film = %e meter. ',t)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.26: Calculation_of_Least_thickness_of_soap_film_for_bright_fringe.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"lambda = 6e-7 // wavelength of light in meter\n",
+"Mu = 1.463 // refractive index of soap film \n",
+"i = 0 // incidence angle in radian \n",
+"r = 0 // refracted angle in radian\n",
+"// Sample Problem 26 on page no. 1.49\n",
+"printf('\n # PROBLEM 26 # \n')\n",
+"n = 1 // for smallest thickness\n",
+"t = ((2 * n - 1) * lambda) / (4 * Mu * cos(r)) // calculation for thickness of soap film\n",
+"printf('\n Standard formula used \n 2*mu*t*cos(r)=(2n-1)*lambda/2. \n')\n",
+"printf('\n Least thickness of soap film for bright fringe = %e meter. ',t)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.27: Calculation_of_Thickness_of_the_film.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"lambda1 = 6.1e-7 // max. wavelength of light in meter\n",
+"lambda2 = 6e-7 // min. wavelength of light in meter\n",
+"Mu = 4 / 3 // refractive index of film \n",
+"i = asin(4 / 5) // incidence angle in radian \n",
+"// Sample Problem 27 on page no. 1.49\n",
+"printf('\n # PROBLEM 27 # \n')\n",
+"r = asin(sin(i) / Mu) // calculation for angle of refraction\n",
+"n = lambda2 / (lambda1 - lambda2) // calculation for order of fringe\n",
+"t = (n * lambda1) / (2 * Mu * cos(r)) // calculation for thickness of film\n",
+"printf('\n Standard formula used \n mu = sin(i)/sin(r),\n 2*mu*t*cos(r) = n*lambda. \n')\n",
+"printf('\n Thickness of the film = %e mm. ',t*1000)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.28: Calculation_of_Thickness_of_wire.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"lambda = 5.893e-7 // wavelenth of light in meter\n",
+"n = 20 // no. of interference fringes are observed \n",
+"Mu = 1 // refractive index of air\n",
+"i = 0 // incidence angle in radian \n",
+"r = 0 // refracted angle in radian \n",
+"// Sample Problem 28 on page no. 1.50\n",
+"printf('\n # PROBLEM 28 # \n')\n",
+"t = (n * lambda) / (2 * Mu) // calculation for thickness of fringe\n",
+"printf('\n Standard formula used \n w = lambda/(2*mu*theta).\n')\n",
+"printf('\n  Thickness of wire = %e mm. ',t*1000)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.29: Calculation_of_Fringe_width.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"lambda = 6e-7 // wavelength of light in meter\n",
+"Mu = 1 // refractive index of air film\n",
+"l = 6e-5 // diameter of wire in meter\n",
+"L = 0.15 // distance of wire from edge in meter\n",
+"i = 0 // incidence angle in radian \n",
+"r = 0 // refracted angle in radian \n",
+"// Sample Problem 29 on page no. 1.50\n",
+"printf('\n # PROBLEM 29 # \n')\n",
+"theta = l / L //calculation for theta\n",
+"fringe_width = lambda / (2 * Mu * theta) // calculation for fringe width\n",
+"printf('\n Standard formula used \n w = lambda/(2*mu*theta).\n')\n",
+"printf('\n Fringe width = %f mm.',fringe_width*1000)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.2: Calculation_No_of_oscillations_of.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 5.896e-7 // wavelength of light in meter\n",
+"L = 2.945e-2 // coherence length in meter\n",
+"// Sample Problem 2 on page no. 1.40\n",
+"printf('\n # PROBLEM 2 # \n')\n",
+"printf('\n Standard formula used \n delta_L = c*delta_t. \n')\n",
+"coherence_time = L / (3 * 10 ^ 8) // calculation for coherence time\n",
+"n = L / lambda // calculation for number of oscillations \n",
+"printf('\n Coherence time = %e sec.',coherence_time)\n",
+"printf('\n No. of oscillations = %e.',n)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.30: Calculation_of_Fringe_width.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"lambda = 4.56e-7 // wavelength of light in meter\n",
+"theta = 1.9e-4 // angle of wedge in radian \n",
+"Mu = 1 // refractive index of air\n",
+"// Sample Problem 30 on page no. 1.51\n",
+"printf('\n # PROBLEM 30 # \n')\n",
+"fringe_width = lambda / (2 * Mu * theta)// calculation for fringe width \n",
+"printf('\n Standard formula used \n w = lambda/(2*mu*alpha).\n')\n",
+"printf('\n Fringe width = %f mm.',fringe_width*1000)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.31: Calculation_of_Fringe_width.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"lambda = 6e-7 // wavelength of light in meter\n",
+"Mu = 1 // refractive index of air film\n",
+"l = 3e-5 // diameter of wire in meter\n",
+"L = 0.15 // distance of wire from edge in meter\n",
+"i = 0 // incidence angle in radian \n",
+"r = 0 // refracted angle in radian \n",
+"// Sample Problem 31 on page no. 1.51\n",
+"printf('\n # PROBLEM 31 # \n')\n",
+"theta = l / L // calculation for theta\n",
+"fringe_width = lambda / (2 * Mu * theta) // calculation for fringe width \n",
+"printf('\n Standard formula used \n w = lambda/ (2*mu*theta).\n')\n",
+"printf('\n Fringe width = %f mm.',fringe_width*1000)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.32: Calculation_of_Distance.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"lambda = 5.890e-7 // wavelength of light in meter\n",
+"theta = 1e-2 // angle of wedge in radian \n",
+"n = 12 // no. of dark fringe\n",
+"Mu = 1 // refractive index of air\n",
+"i = 0 // incidence angle in radian\n",
+"r = 0 // refracted angle in radian\n",
+"// Sample Problem 32 on page no. 1.51\n",
+"printf('\n # PROBLEM 32 # \n')\n",
+"x = ( n * lambda) / (2 * theta) // calculation for distance\n",
+"printf('\n Standard formula used \n x = n*lambda/(2*theta).\n')\n",
+"printf('\n Distance = %f mm. ',x*1000)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.33: Calculation_of_Angle_of_wedge.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"lambda = 5.5e-7 // wavelength of light in meter\n",
+"w = 2e-5 // fringe width in meter\n",
+"Mu = 1.5 // refractive index of film\n",
+"i = 0 // incidence angle in radian\n",
+"r = 0 // refracted angle in radian\n",
+"// Sample Problem 33 on page no. 1.52\n",
+"printf('\n # PROBLEM 33 # \n')\n",
+"theta = lambda / (2 * Mu * w)// calculation for the angle of the film\n",
+"printf('\n Standard formula used \n w = lambda/(2*mu*theta).\n')\n",
+"printf('\n Angle of wedge = %f degree. ',theta * 180/ %pi)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.34: Calculation_of_Wavelength_of_light.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"d1 = 5.9e-3 // diameter of 15th ring in meter\n",
+"d2 = 3.36e-3 // diameter of 5th ring in meter\n",
+"R = 1 // redius of the plano-convex lens in meter\n",
+"// Sample Problem 34 on page no. 1.52\n",
+"printf('\n # PROBLEM 34 # \n') \n",
+"p = 15 - 5\n",
+"lambda = ((d1^2) - (d2^2)) / (4 * p * R) // calculation for wavelength of light\n",
+"printf('\n Standard formula used \n lambda = (d1^2-d2^2)/(4*p*R).\n')\n",
+"printf('\n Wavelength of light = %f A.',lambda*1e10)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.35: Calculation_of_Wavelength_of_light.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"d1 = 2e-3 // diameter of 10th ring in meter\n",
+"d2 = 3e-3 // diameter of 20th ring in meter\n",
+"f = 0.9 // focal length of the plano-convex lens in meter\n",
+"mu = 1.5 // refractive index of lens\n",
+"// Sample Problem 35 on page no. 1.52\n",
+"printf('\n # PROBLEM 35 # \n') \n",
+"p = 20 - 10\n",
+"R = (f * (mu - 1)) // calculation for radius of convex surface of lens\n",
+"lambda = ((d2^2) - (d1^2)) / (4 * p * R)\n",
+"printf('\n Standard formula used \n lambda = ((d2^2) - (d1^2)) / (4 * p * R).\n')\n",
+"printf('\n Wavelength of light = %f nm.',lambda*1e9)\n",
+"//Answer in the book:2777 nm\n",
+"//Answer in the program:277.77778 nm"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.36: Calculation_of_Diameter_of_7th_bright_ring.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"lambda = 5.896e-7 // wavelength of light in meter\n",
+"f = 1 // focal length of the plano-convex lens in meter\n",
+"mu = 1.5 // refractive index of lens \n",
+"n = 7 // no. of bright ring\n",
+"// Sample Problem 36 on page no. 1.53\n",
+"printf('\n # PROBLEM 36 # \n') \n",
+"p = 20 - 10\n",
+"R = (f * (mu - 1)) * 2 // calculation for radius of lens\n",
+"D = sqrt(4 * n * lambda * R) // calculation for diameter of 7th ring \n",
+"printf('\n Standard formula used \n Dn^2 = 4n*lambda*R. \n')\n",
+"printf('\n Diameter of 7th bright ring = %e meter.',D)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.37: Calculation_of_Diameter_of_dark_ring.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"lambda1 = 6e-7 // wavelength of first light in meter\n",
+"lambda2 = 4.8e-7 // wavelength of second light in meter\n",
+"r = 0.96 // radius of curvature of curved surface of lens in meter\n",
+"// Sample Problem 37 on page no. 1.53\n",
+"printf('\n # PROBLEM 37 # \n') \n",
+"n = lambda2 / (lambda1 - lambda2) // calculation for order of fringe\n",
+"D = sqrt(4 * (n + 1) * lambda2 * r) // calculation for diameter of ring\n",
+"printf('\n Standard formula used \n n^2 = 4n*lambda*R. \n')\n",
+"printf('\n Diameter of (n +1)th dark ring of lambda2. = %e meter.',D)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.38: Calculation_of_Diameter_of_nth_dark_ring.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"lambda1 = 6e-7 // wavelength of first light in meter\n",
+"lambda2 = 5.9e-7 // wavelength of second light in meter\n",
+"r = 0.9 // radius of curvature of curved surface of lens in meter\n",
+"// Sample Problem 38 on page no. 1.54\n",
+"printf('\n # PROBLEM 38 # \n') \n",
+"n = lambda2 / (lambda1 - lambda2) // calculation for order of ring\n",
+"D = sqrt(4 * (n + 1) * lambda1 * r) // calculation for diameter of ring\n",
+"printf('\n Standard formula used \n n^2 = 4n*lambda*R.\n')\n",
+"printf('\n Diameter of nth dark ring of lambda1 = %f meter.',D)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.39: Calculation_of_Refractive_index_of_liquid.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"lambda = 5.896e-7 // wavelength of light in meter\n",
+"D = 4e-3 // diameter of 7th brighter fringe in m\n",
+"R = 1 // radius of curvature in m\n",
+"// Sample Problem 39 on page no. 1.54\n",
+"printf('\n # PROBLEM 39 # \n') \n",
+"n = 7 // for seventh brighter fringe\n",
+"mu = 2*(2*n-1)*lambda*R / D^2 // calculation for refractive index of liquid\n",
+"printf('\n Standard formula used \n mu = 2*(2*n-1)*lambda*R / D^2.\n')\n",
+"printf('\n Refractive index of liquid = %f.',mu)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.3: Calculation_of_Coherence_time_and_Line_width_and_Frequency_stability.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 6.058e-7 // wavelength of light in meter\n",
+"L = 0.2 // coherence length in meter\n",
+"// Sample Problem 3 on page no. 1.40\n",
+"printf('\n # PROBLEM 3 # \n')\n",
+"printf('\n Standard formula used \n f = c/lambda. \n')\n",
+"line_width = (lambda ^ 2) / L//calculation for line width\n",
+"f_spread = (3 * 10 ^ 8) / L// calculation for frequency spread\n",
+"f = (3 * 10 ^ 8) / lambda // calculation for frequency\n",
+"f_stability = f_spread / f // calculation for frequency stability\n",
+"coherence_time = L / (3 * 10 ^ 8) // calculation for coherence time\n",
+"printf('\n Coherence time = %e sec',coherence_time)\n",
+"printf('\n Line width = %e meter',line_width)\n",
+"printf('\n Frequency stability = %e', f_stability)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.40: Calculation_of_Refractive_index_of_liquid.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"D1 = 3e-3 // diameter of nth dark fringe when liquid is absent between the lens and the plate in m\n",
+"D2 = 2.5e-3 // diameter of nth dark fringe when liquid is introduced between the lens and the plate in m\n",
+"c = 3e8 // velocity of light in vacuum in m/sed\n",
+"// Sample Problem 40 on page no. 1.54\n",
+"printf('\n # PROBLEM 40 # \n') \n",
+"mu = D1^2 / D2^2// calculation for refractive index\n",
+"v = 3e8 / mu // calculation for velocity of light \n",
+"printf('\n Standard formula used \n mu = D1^2 / D2^2. \n v = 3e8 / mu. \n')\n",
+"printf('\n Refractive index of liquid = %f.\n velocity of light in the liquid = %e m/sec.',mu,v)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.41: Calculation_of_Refractive_index_of_liquid.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"lambda = 5.896e-7 // wavelength of light in meter\n",
+"D = 5.1e-3 // diameter of 16th brighter fringe in m\n",
+"R = 1 // radius of curvature in m\n",
+"// Sample Problem 41 on page no. 1.55\n",
+"printf('\n # PROBLEM 41 # \n') \n",
+"n = 16 // for sixteenth brighter fringe\n",
+"mu = 4*n*lambda*R / D^2 // calculation for refractive index of liquid\n",
+"printf('\n Standard formula used \n mu = 4*n*lambda*R / D^2.\n')\n",
+"printf('\n Refractive index of liquid = %f.',mu)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.42: Calculation_of_The_radius_of_smallest_dark_ring.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"lambda = 6.3e-7 // wavelength of light in meter\n",
+"mu = 1.63 // refractive index of liquid \n",
+"R = 0.9 // the radius of curvature of convex lens in meter\n",
+"// Sample Problem 42 on page no. 1.55\n",
+"printf('\n # PROBLEM 42 # \n') \n",
+"r = sqrt(lambda*R/mu) // calculation for the radius of smallest dark ring\n",
+"printf('\n Standard formula used \n r = sqrt(n*lambda*R/mu). \n')\n",
+"printf('\n The radius of smallest dark ring = %f mm.',r*1000)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.43: Calculation_of_the_ratio_refractive_index_of_media.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"r = 10/7 // ratio of nth ring diameter for two media\n",
+"// Sample Problem 43 on page no. 1.55\n",
+"printf('\n # PROBLEM 43 # \n') \n",
+"R = (1/r)^2 // calculation for the ratio of refractive index of media\n",
+"printf('\n Standard formula used \n mu1/mu2 = D2/D1. \n')\n",
+"printf('\n the ratio refractive index of media = %f:100.',R*100)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.44: Calculation_of_Wavelength_of_light.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"R = 0.9 // radius of curvature of the lower face of the lens in meter\n",
+"D = 4.8e-3 // diameter of the 10th dark ring in meter\n",
+"// Sample Problem 44 on page no. 1.56\n",
+"printf('\n # PROBLEM 44 # \n') \n",
+"n = 10 // for 10th dark ring\n",
+"lambda = D^2 / (4 * n * R) // calculation for wavelength of light\n",
+"printf('\n Standard formula used \n lambda = D^2 / (4 * n * R). \n')\n",
+"printf('\n Wavelength of light = %f A.',lambda * 1e10)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.45: Calculation_of_Refractive_index_of_liquid.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"r = 1/2 // ratio of 5th ring diameter when no liquid between plane glass plate and convex lens and when the liquid between glass plate and convex lens\n",
+"// Sample Problem 45 on page no. 1.56\n",
+"printf('\n # PROBLEM 45 # \n') \n",
+"R = (1/r)^2 // calculation for refractive index of liquid\n",
+"printf('\n Standard formula used \n mu1/mu2 = D2/D1. \n')\n",
+"printf('\n Refractive index of liquid = %f. ',R)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.46: Calculation_of_Distance_between_5th_and_15th_dark_ring.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"R = 1 // radius of curvature of lens of both side in meter\n",
+"lambda = 5.4e-7 // wavelength of monochromatic light in meter\n",
+"// Sample Problem 46 on page no. 1.56\n",
+"printf('\n # PROBLEM 46 # \n') \n",
+"n1 = 5 // for 5th dark ring\n",
+"n2 = 15 // for 10th dark ring\n",
+"r1 = sqrt((n1*lambda)/(1/R + 1/R)) // calculation for radius of 5th dark ring\n",
+"r2 = sqrt((n2*lambda)/(1/R + 1/R)) // calculation for radius of 15th dark ring\n",
+"d = r2 - r1 // calculation for distance between 5th and 15th dark ring\n",
+"printf('\n Standard formula used \n r = sqrt((n*lambda)/(1/R + 1/R)). \n')\n",
+"printf('\n Distance between 5th and 15th dark ring = %f cm.',d * 100)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.47: Calculation_of_Refractive_index_of_mica.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"x = 2.5e-5 // distance moved by movable mirror in meter\n",
+"t = 5e-5 // thickness of mica sheet in meter\n",
+"// Sample Problem 47 on page no. 1.57\n",
+"printf('\n # PROBLEM 47 # \n') \n",
+"mu = x / t + 1 // calculation for refractive index of mica\n",
+"printf('\n Standard formula used \n mu = x / t + 1. \n')\n",
+"printf('\n Refractive index of mica = %f.',mu)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.48: Calculation_of_Wavelength_of_light.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"x = 6e-5 // distance moved by movable mirror in meter\n",
+"N = 200 // no. of fringes crossed the field of view \n",
+"// Sample Problem 48 on page no. 1.57\n",
+"printf('\n # PROBLEM 48 # \n') \n",
+"lambda = (2 * x) / N // calculation for wavelength of light\n",
+"printf('\n Standard formula used \n lambda = (2 * X) / N. \n')\n",
+"printf('\n Wavelength of light = %f A.',lambda * 1e10)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.49: Calculation_of_Thickness_of_the_plate.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"n = 50 // no. of bands crosses the line of observation \n",
+"lambda = 5.896e-7 // wavelength of light in meter\n",
+"mu = 1.4 // refractive index \n",
+"// Sample Problem 49 on page no. 1.57\n",
+"printf('\n # PROBLEM 49 # \n') \n",
+"t = n*lambda / (2*(mu-1)) // calculation for thickness of the plate\n",
+"printf('\n Standard formula used \n t = n*lambda /2*(mu-1)\n')\n",
+"printf('\n Thickness of the plate = %e m.',t)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.4: Calculation_of_Coherence_length.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda_D = 5.5e-13 // Doppler width of orange light in meter\n",
+"lambda = 6.058e-7 // wavelength of light in meter\n",
+"// Sample Problem 4 on page no. 1.41\n",
+"printf('\n # PROBLEM 4 # \n')\n",
+"printf('\n Standard formula used \n delta_L = lambda^2/delta_lambda. \n')\n",
+"coherence_length = (lambda ^ 2) / lambda_D// calculation for coherence light\n",
+"printf('\n Coherence length = %f meter',coherence_length)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.50: Calculation_of_The_path_difference.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"n = 50 // no. of bands crosses the line of observation \n",
+"lambda1 = 5.896e-7 // max. wavelength of light in meter\n",
+"lambda2 = 5.89e-7 // min. wavelength of light in meter\n",
+"// Sample Problem 50 on page no. 1.57\n",
+"printf('\n # PROBLEM 50 # \n') \n",
+"x = lambda1 * lambda2 /(lambda1 - lambda2) // calculation for the path difference\n",
+"printf('\n Standard formula used \n t = n*lambda /2*(mu-1)\n')\n",
+"printf('\n The path difference = %f mm.',x*10^3)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.51: Calculation_of_Wavelength_of_monochromatic_light.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"x = 2.948e-5 // distance moved by movable mirror in meter\n",
+"n = 100 // no. of fringes cross the field of view \n",
+"// Sample Problem 51 on page no. 1.58\n",
+"printf('\n # PROBLEM 51 # \n') \n",
+"lambda = 2*x/n // calculation for wavelength of monochromatic light\n",
+"printf('\n Standard formula used \n lambda = 2*x/n. \n')\n",
+"printf('\n Wavelength of monochromatic light = %f A.',lambda * 1e10)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.52: Calculation_of_The_distance_through_which_the_movable_mirror_is_move.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"lambda1 = 5.896e-7 // max. wavelength of light in meter\n",
+"lambda2 = 5.89e-7 // min. wavelength of light in meter\n",
+"// Sample Problem 52 on page no. 1.58\n",
+"printf('\n # PROBLEM 52 # \n') \n",
+"x = lambda1 * lambda2 /(2*(lambda1 - lambda2)) // calculation for the path difference\n",
+"printf('\n Standard formula used \n x = lambda1 * lambda2 /2*(lambda1 - lambda2).\n')\n",
+"printf('\n The distance through which the movable mirror is move = %f mm.',x*10^3)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.53: Calculation_of_Difference_between_two_wavelengths.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"x = 2.945e-4 // distance moved by movable mirror in meter\n",
+"lambda = 5.893e-7 // mean wavelength of light in meter\n",
+"// Sample Problem 53 on page no. 1.58\n",
+"printf('\n # PROBLEM 53 # \n') \n",
+"delta_lambda = lambda^2 / (2*x) // calculation for difference between two wavelengths\n",
+"printf('\n Standard formula used \n delta_lambda = lambda^2 / (2*x). \n')\n",
+"printf('\n Difference between two wavelengths = %f A.',delta_lambda*1e10)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.54: Calculation_of_Refractive_index_of_gas.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given That\n",
+"n = 140 // no. of shift in fringe\n",
+"lambda = 5.46e-7 // wavelength of light in meter\n",
+"t = 0.2 // length of tube in meter\n",
+"// Sample Problem 54 on page no. 1.58\n",
+"printf('\n # PROBLEM 54 # \n') \n",
+"mu = (n*lambda)/(2*t) + 1 // calculation for refractive index of gas\n",
+"printf('\n Standard formula used \n mu = (n*lambda)/(2*t) + 1. \n')\n",
+"printf('\n  Refractive index of gas = %f.',mu)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.5: EX1_5.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda1 = 5.461e-7 // wavelength of light emitted by mercury vapour lamp in meter\n",
+"band_width1 = 6e8 // band width for mercury vapour lamp in Hz\n",
+"lambda2 = 6.328e-7 // the operating wavelength of light for He Ne laser \n",
+"band_width2 = 1e6 // band width for laser in Hz\n",
+"// Sample Problem 5 on page no. 1.41\n",
+"printf('\n # PROBLEM 5 # \n')\n",
+"delta_lambda1 = (lambda1^2 * band_width1) / 3e8 // calculation for difference between two wavelength for mercury vapour\n",
+"delta_L1 = lambda1^2 / delta_lambda1 // calculation for coherence length for mercury vapour lamp\n",
+"delta_lambda2 = (lambda2^2 * band_width2) / 3e8 // calculation for difference between two wavelength for He Ne laser\n",
+"delta_L2 = lambda2^2 / delta_lambda2 // calculation for coherence length for He Ne laser\n",
+"R = delta_L1/delta_L2 // calculation for ratio of coherence length of mercury vapour lamp to the coherence length of He Ne laser\n",
+"printf('\n Standard formula used \n delta_lambda = lambda^2*band_width / c, \n coherence length = lambda^2/delta_lambda.\n')\n",
+"printf('\n The ratio of coherence length of mercury vapour lamp to the coherence length of He Ne laser = 1:%d. ',1/R)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.6: Calculation_of_Coherence_length_of_laser.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"band_width = 3000 // band width of laser in hertz\n",
+" // Sample Problem 6 on page no. 1.42\n",
+"printf('\n # PROBLEM 6 # \n')\n",
+"printf('\n Standard formula used \n delta_L = c*delta_t. \n')\n",
+"coherence_length = (3 * 10 ^ 8) / band_width//calculation for coherence length \n",
+"printf('\n Coherence length of laser = %e meter.',coherence_length)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.7: EX1_7.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 6.328e-7 // wavelength of monochromatic light in meter\n",
+"t = 1e-10 // chopping time in sec\n",
+"// Sample Problem 7 on page no. 1.42\n",
+"printf('\n # PROBLEM 7 # \n')\n",
+"coherence_length = (3 * 10 ^ 8) * t // calculation for coherence length of monochromatic light \n",
+"band_width = 1 / t // calculation for band width \n",
+"line_width = ((lambda ^ 2) * band_width) / (3 * 10 ^ 8) // calculation for line width \n",
+"printf('\n Standard formula used \n coherence_length = (3 * 10 ^ 8) * t. \n line_width = ((lambda ^ 2) * band_width) / (3 * 10 ^ 8). \n')\n",
+"printf('\n Coherence length of monochromatic light = %e meter. \n band width = %e Hz. \n line width = %f A.',coherence_length, band_width, line_width*1e10)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.8: Calculation_of_Coherence_time_of_red_cadmium_line_and_Spectral_line_width.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 6.438e-7 // wavelength of red cadmium line in meter\n",
+"L = 3.8e-1 // coherence length in meter\n",
+"// Sample Problem 8 on page no. 1.42\n",
+"printf('\n # PROBLEM 8 # \n')\n",
+"printf('\n Standard formula used \n delta_L = c*delta_t. \n')\n",
+"coherence_time = L / (3 * 10 ^ 8)// calculation for coherence time\n",
+"spectral_line_width = (lambda ^ 2) / L // calculation for spectral line width\n",
+"printf('\n Coherence time of red cadmium line = %e sec. \n Spectral line width = %e meter.',coherence_time,spectral_line_width)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.9: Calculation_of_Ratio_of_maximum_intensity_with_minimum_intensity.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"ratio = 16 // ratio of intensities of two waves\n",
+"// Sample Problem 9 on page no. 1.43\n",
+"printf('\n # PROBLEM 9 # \n')\n",
+"printf('\n Standard formula used \n I = k*a^2. \n')\n",
+"a1 = sqrt(ratio) // by the formula amplitude = sqrt(intensity)\n",
+"a2 = 1\n",
+"R = ((a1 + a2) ^ 2) / ((a1 - a2) ^ 2)// calculation for ratio of maximum intensity with minimum intensity\n",
+"printf('\n Ratio of maximum intensity with minimum intensity = %f',R)"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Engineering_Physics_by_H_K_Malik/10-ELECTROMAGNETISM.ipynb b/Engineering_Physics_by_H_K_Malik/10-ELECTROMAGNETISM.ipynb
new file mode 100644
index 0000000..27aa1c7
--- /dev/null
+++ b/Engineering_Physics_by_H_K_Malik/10-ELECTROMAGNETISM.ipynb
@@ -0,0 +1,445 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 10: ELECTROMAGNETISM"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 10.15: Calculation_of_The_total_charge_within_volume.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"n = 2000 // flux lines enter in given volume  in Vm\n",
+"n_ = 4000 // flux lines diverge from given volume in Vm\n",
+"e0 = 8.85e-12 // permittivity of space\n",
+"// Sample Problem 15 on page no. 10.42\n",
+"printf('\n # PROBLEM 15 # \n')\n",
+"fi = n_ - n\n",
+"q = e0 * fi\n",
+"printf('Standard formula used \n fi = q/e_')\n",
+"disp(q,' The total charge within volume(in C) = ')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 10.16: Calculation_of_The_total_charge_enclosed_by_closed_surface.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"n = 20000 // flux lines entering in given volume in Vm\n",
+"n_ = 45000 // flux lines entering out from given volume in Vm\n",
+"e0 = 8.85e-12 // permittivity of space\n",
+"// Sample Problem 16 on page no. 10.42\n",
+"printf('\n # PROBLEM 16 # \n')\n",
+"fi = n_ - n\n",
+"q = e0 * fi\n",
+"printf('Standard formula used \n fi= q/e_. \n')\n",
+"printf('The total charge enclosed by closed surface is %e C.',q)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 10.17: Calculation_of_Electric_flux.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"q = 13.5e-6 // charge enclosed at the centre of cube in C\n",
+"l = 6 // length of the side of cube in cm\n",
+"e0 = 8.85e-12 // permittivity of space\n",
+"// Sample Problem 17 on page no. 10.43\n",
+"printf('\n # PROBLEM 17 # \n')\n",
+"fi = q / e0\n",
+"fi_ = fi / 6\n",
+"q = e0 * fi\n",
+"printf('Standard formula used \n fi=q/e_.\n')\n",
+"printf('Electric flux through the whole volume of the cube is %e Nm^2/C.\n Electric flux through one face of the cube is %e Nm^2/C.',fi,fi_)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 10.18: Calculation_of_Electric_flux_through_each_surface_of_the_cube.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"q = 11 // charge enclosed at the centre of cube in C\n",
+"l = 5 // length of the side of cube in cm\n",
+"e0 = 8.85e-12 // permittivity of space\n",
+"// Sample Problem 18 on page no. 10.43\n",
+"printf('\n # PROBLEM 18 # \n')\n",
+"fi_ = (q / e0) / 6\n",
+"printf('\nStandard formula used \n fi=q/e_\n')\n",
+"printf(' Electric flux through each surface of the cube = %e Nm^2/C.',fi_)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 10.19: Calculation_of_Electric_field_intensity.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"q = 1e-8 // charge uniformly spread over metallic sphere in C\n",
+"r = .1 //radius of sphere in m\n",
+"d = 7 // distance of a point from centre of the sphere in cm\n",
+"d_ = .5 // distance of another point from centre of the sphere in m\n",
+"e0 = 8.85e-12 // permittivity of space\n",
+"// Sample Problem 19 on page no. 10.43\n",
+"printf('\n # PROBLEM 19 # \n')\n",
+"E1 = (1 / (4 * %pi * e0) * (q / r^2))\n",
+"E2 = 0 //because sphere is metallic\n",
+"E3 = (1 / (4 * %pi * e0) * (q / d_^2))\n",
+"printf('Standard formula used \n E = (1 / (4 * pi * e0) * (q / r^2)). \n')\n",
+"printf(' Electric field intensity-\n (1) On the surface of the sphere = %e N/C,\n (2) At first point = %d N/C,\n (3) At second point = %e N/C',E1,E2,E3)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 10.20: Calculation_of_Electric_field.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"q = 1.6e-19 // charge on a proton in C\n",
+"d = 1e-10 // distance of a point from proton in m\n",
+"e0 = 8.85e-12 // permittivity of space\n",
+"// Sample Problem 20 on page no. 10.44\n",
+"printf('\n # PROBLEM 20 # \n')\n",
+"E = (1 / (4 * %pi * e0)) * (q / d^2)\n",
+"printf('Standard formula used \n E = (1 / (4 * pi * e0)) * (q / d^2).\n')\n",
+"printf(' Electric field = %e V/m.',E)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 10.21: Calculation_of_Energy_gained_by_alpha_particle.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"v = 1000 // potential through which alpha particle accelerated in V\n",
+"q = 3.2e-19 // charge on an alpha particle in C\n",
+"e0 = 8.85e-12 // electric permittivity of space\n",
+"// Sample Problem 21 on page no. 10.44\n",
+"printf('\n # PROBLEM 21 # \n')\n",
+"E = q * v\n",
+"printf('Standard formula used \n E = q * v.\n')\n",
+"printf(' Energy gained by alpha particle = %e J.',E)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 10.22: Calculation_of_Potential_and_Potential_energy_and_Potential_difference.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"q = 1.6e-19 // charge on a proton in C\n",
+"d = 1e-10 // distance of a point from proton in m\n",
+"d_ = 2e-11 // distance of another point from proton in m\n",
+"e0 = 8.85e-12 // permittivity of space\n",
+"// Sample Problem 22 on page no. 10.44\n",
+"printf('\n # PROBLEM 22 # \n')\n",
+"v = (1 / (4 * %pi * e0)) * (q / d)//calculation for potential at first point\n",
+"E = -q * v//calculation for energy at first point in J\n",
+"delta_v = (1 / (4 * %pi * e0)) * q * ((1 / d_) - (1 / d))//calculation for potential difference between points\n",
+"printf('Standard formula used \n V=(1/(4*pi*e_))*q/r,\n E=-(1/(4*pi*e_))*q^2/r.\n')\n",
+"printf(' Potential energy at first point = %f eV.\n Potential difference between points = %f V.',E/q,delta_v)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 10.23: Calculation_of_Radius_of_equipotential_surface.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"q = 1.5e-6 // charge in C\n",
+"v = 30 // potential of a surface in V\n",
+"e0 = 8.85e-12 // permittivity of space\n",
+"// Sample Problem 23 on page no. 10.45\n",
+"printf('\n # PROBLEM 23 # \n')\n",
+"r = (1 / (4 * %pi * e0)) * (q / v)\n",
+"printf('Standard formula used \n v = (1/(4*pi*e_)*(q/r)).\n')\n",
+"printf(' Radius of equipotential surface = %d m.',ceil(r))"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 10.24: Calculation_of_The_value_of_poynting_vector_at_the_surface_of_the_sun.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"p = 3.8e26 // power radiated by sun in W\n",
+"r = 7e8 // radius of sun in m\n",
+"e0 = 8.85e-12 // permittivity of space\n",
+"// Sample Problem 24 on page no. 10.45\n",
+"printf('\n # PROBLEM 24 # \n')\n",
+"s = p / (4 * %pi * r^2)\n",
+"printf('Standard formula used \n s = p / (4 * pi * r^2).\n')\n",
+"printf(' The value of poynting vector at the surface of the sun = %e W/m^2.',s)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 10.28: EX10_28.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"s = 2 // energy received by the earth in cal/cm^2.min\n",
+"e0 = 8.85e-12 // electric permittivity of space\n",
+"mu0 = 1.2567e-6 // magnetic permittivity of space\n",
+"c = 3e8 // speed of light in meter/sec\n",
+"// Sample Problem 28 on page no. 10.47\n",
+"printf('\n # PROBLEM 28 # \n')\n",
+"r = sqrt(mu0 / e0)\n",
+"P = s*4.2/(60*1e-4)\n",
+"E = sqrt(P*r)\n",
+"H = E/r\n",
+"printf('Standard formula used \n P = E*H.\n')\n",
+"printf(' Magnitude of electric field vector = %f v/m.\n Magnitude of magnetic field vector = %f A/m.',E * sqrt(2),H*sqrt(2))"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 10.29: Calculation_of_Magnitude_of_electric_field_vector.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"H = 1 // magnitude of magnetic field vector A/m\n",
+"e0 = 8.85e-12 // electric permittivity of space\n",
+"mu0 = 1.2567e-6 // magnetic permittivity of space\n",
+"c = 3e8 // speed of light in meter/sec\n",
+"// Sample Problem 29 on page no. 10.48\n",
+"printf('\n # PROBLEM 29 # \n')\n",
+"r = sqrt(mu0 / e0) // ratio of E,H\n",
+"E = H * r\n",
+"printf('Standard formula used \n H_/E_=sqrt(e_/mu_).\n')\n",
+"printf(' Magnitude of electric field vector = %f v/m.',E)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 10.31: Calculation_of_Average_value_of_the_intensity_of_electric_field_of_radiation.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"p = 1000 // power of lamp in W\n",
+"d = 2 // distance of a point from lamp in meter\n",
+"e0 = 8.85e-12 // electric permittivity of space\n",
+"mu0 = 1.2567e-6 // magnetic permittivity of space\n",
+"c = 3e8 // speed of light in meter/sec\n",
+"// Sample Problem 31 on page no. 10.48\n",
+"printf('\n # PROBLEM 31 # \n')\n",
+"s = p / (4 * %pi * d^2) //calculation for \n",
+"r = sqrt(mu0 / e0) // ratio of E,H\n",
+"E = sqrt(s * r)//calculation for average value of intensity of electric field of radiation\n",
+"printf('Standard formula used \n E_/H_=sqrt(mu_/e_),\nP=E*H.\n')\n",
+"printf(' Average value of the intensity of electric field of radiation = %f v/m.',E)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 10.32: Calculation_of_Refractive_index_of_distilled_water_and_Speed_of_light_in_water.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"k = 81 // relative permittivity of water \n",
+"c = 3e8 // speed of light in meter/sec\n",
+"// Sample Problem 32 on page no. 10.49\n",
+"printf('\n # PROBLEM 32 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' mu_ = ( mu*epsilon /(mu_0/*psilon_0))^1/2  \n \n' )\n",
+"mu = sqrt(k)\n",
+"v = c / mu\n",
+"printf(' Refractive index of distilled water is %d .\n Speed of light in water is %e m/sec.',mu,v)"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Engineering_Physics_by_H_K_Malik/11-THEORY_OF_RELATIVITY.ipynb b/Engineering_Physics_by_H_K_Malik/11-THEORY_OF_RELATIVITY.ipynb
new file mode 100644
index 0000000..c02424e
--- /dev/null
+++ b/Engineering_Physics_by_H_K_Malik/11-THEORY_OF_RELATIVITY.ipynb
@@ -0,0 +1,987 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 11: THEORY OF RELATIVITY"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 11.10: Calculation_of_Velocity.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"u = 3e8 // speed of signal in meter/sec\n",
+"// Sample Problem 10 on page no. 11.21\n",
+"printf('\n # PROBLEM 10 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' u_x = u_x_ + v / (1+ v*u_x_/c^2). \n ')\n",
+"u_ = (u + 3e8) / (1 + (u * 3e8) / 3e8^2)\n",
+"printf('\n Velocity is %d*c, hence we can say that no signal can travel faster than light.',u_/3e8)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 11.11: Calculation_of_Speed_of_particle.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"r = 2.25 // ratio of mass of particle to the rest mass\n",
+"// Sample Problem 11 on page no. 11.22\n",
+"printf('\n # PROBLEM 11 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' m = m_0/((1-v^2/c^2)^1/2) \n ')\n",
+"v = 3e8 * sqrt(1 - (1 / r)^2)\n",
+"printf('\n Speed of particle is %e meter/sec.',v)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 11.12: Calculation_of_Velocity_of_particle.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"r = 2 // ratio of kinetic energy of body to its rest mass\n",
+"// Sample Problem 12 on page no. 11.22\n",
+"printf('\n # PROBLEM 12 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' m = m_0/((1-v^2/c^2)^1/2) \n KE = (m-m_0)*c^2  \n ')\n",
+"v = 3e8 * sqrt(1 - (1 / (r + 1))^2)\n",
+"printf('\n Velocity of particle is %f c.',v/3e8)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 11.13: Calculation_of_Kinetic_energy_of_electron_and_Momentum_of_particle.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"r = 11 // ratio of mass of particle to the rest mass of electron\n",
+"// Sample Problem 13 on page no. 11.22\n",
+"printf('\n # PROBLEM 13 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' m = m_0/((1-v^2/c^2)^1/2) \n KE = (m-m_0)*c^2  \n ')\n",
+"KE = (r - 1) * 9.1e-31 * 3e8^2 / (1.6e-19)\n",
+"m = 3e8 * sqrt(1 - (1 / r)^2) * 9.1e-31 * 11\n",
+"printf('\n Kinetic energy of electron is %f MeV.\n Momentum of particle is %e N-sec.',KE/1e6,m)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 11.14: Calculation_of_Velocity_of_electron.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"m = 1.67e-27  // mass of electron in kg\n",
+"m_ = 9.1e-31 // rest mass of electron in kg\n",
+"// Sample Problem 14 on page no. 11.23\n",
+"printf('\n # PROBLEM 14 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' m = m_0/((1-v^2/c^2)^1/2) \n ')\n",
+"v = 3e8 * sqrt(1 - (m_ / m)^2)\n",
+"printf('\n Velocity of electron is %f meter/sec.',v)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 11.15: EX11_15.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"E = 0.1 // kinetic speed of electron in Mev\n",
+"// Sample Problem 15 on page no. 11.23\n",
+"printf('\n # PROBLEM 15 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' m = m_0/((1-v^2/c^2)^1/2) \n KE = (m-m_0)*c^2  \n KE = 1/2*m*v^2 \n')\n",
+"v_ = sqrt(2 * (E * 1.6e-13) / 9.1e-31)\n",
+"v = 3e8 * sqrt(1 - (1 / (1 + (1.6e-13 * E) / (9.1e-31 * 3e8^2)))^2)\n",
+"printf('\n Speed according to classical mechanics is %e meter/sec.\n Speed according to relativistic mechanics is %e meter/sec.',v_,v)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 11.17: Calculation_of_Velocity_of_particle.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"r1 = 3 // ratio of kinetic energy of body to its rest mass in first case\n",
+"r2 = 1 // ratio of kinetic energy of body to its rest mass in second case\n",
+"// Sample Problem 17 on page no. 11.24\n",
+"printf('\n # PROBLEM 17 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' m = m_0/((1-v^2/c^2)^1/2) \n KE = (m-m_0)*c^2 \n')\n",
+"v1 = 3e8 * sqrt(1 - (1 / (r1 + 1))^2)\n",
+"v2 = 3e8 * sqrt(1 - (1 / (r2 + 1))^2)\n",
+"printf('\n Velocity of particle if kinetic energy is %d times of rest mass energy  is %e meter/sec.\n Velocity of particle if kinetic energy is %d times of rest mass energy  is %e meter/sec.\n',r1,v1,r2,v2)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 11.19: Calculation_of_Speed_of_electron_and_Mass_of_electron.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"E = 1.5 // kinetic energy of electron in Mev\n",
+"// Sample Problem 19 on page no. 11.25\n",
+"printf('\n # PROBLEM 19 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' m = m_0/((1-v^2/c^2)^1/2) \n KE = (m-m_0)*c^2 \n')\n",
+"v = 3e8 * sqrt(1 - (1 / (1 + (1.6e-19 * 2e6) / (9.1e-31 * 3e8^2)))^2)\n",
+"m = (E * 1.6e-13 / (3e8)^2) + 9.1e-31\n",
+"printf('\n Speed of electron is %e meter/sec.\n Mass of electron is %e kg.',v,m)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 11.20: Calculation_of_Length_of_meter_stick.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"r = 3 / 2 // ratio of mass of metre stick to the rest mass of metre stick\n",
+"// Sample Problem 20 on page no. 11.26\n",
+"printf('\n # PROBLEM 20 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' m = m_0/((1-v^2/c^2)^1/2) \n l = l_0/((1-v^2/c^2)^1/2)  \n')\n",
+"l = 1 * (1 / r)\n",
+"printf('\n Length of meter stick is %f meter if mass is %f times of its rest mass.',l,r)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 11.21: Calculation_of_Velocity_of_a_frame_with_respect_to_other_frame.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"r = 1 / 2 // ratio of area of circular lamina in frame S_ to the ratio of area of circular lamina in frame S\n",
+"// Sample Problem 21 on page no. 11.26\n",
+"printf('\n # PROBLEM 21 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' d = d_0/((1-v^2/c^2)^1/2)  \n')\n",
+"v = 3e8 * sqrt(1 - r^2)\n",
+"printf('\n Velocity of frame S_ w.r.t. frame S is %e meter/sec.',v)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 11.22: Calculation_of_Speed_of_clock.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"t = 1 // lose in time in an hour in minute\n",
+"// Sample Problem 22 on page no. 11.27\n",
+"printf('\n # PROBLEM 22 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' t = t_0/((1-v^2/c^2)^1/2) \n')\n",
+"v = 3e8 * sqrt(1 - ((60 - t) / 60)^2)\n",
+"printf('\n Speed of clock is %e meter/sec.',v)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 11.23: Calculation_of_Distance_travel_by_the_beam.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"t_ = 2.5e-8 // proper life of pi+ mesons in sec\n",
+"v = 2.4e8 // velocity of beam of mesons in m/sec\n",
+"r = 1 / exp(2) // ratio of final flux to initial flux of the meson beam\n",
+"// Sample Problem 23 on page no. 11.27\n",
+"printf('\n # PROBLEM 23 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' t = t_0/((1-v^2/c^2)^1/2) \n N = N_0*e^(-t/tau) \n')\n",
+"t = t_ / sqrt(1 - (v / 3e8)^2)\n",
+"T = t * log(1 / r)\n",
+"d = T * v\n",
+"printf('\n Distance travel by the beam is %f meter.',d)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 11.24: Calculation_of_Velocity_of_rocket_with_respect_to_earth.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"v = 1.8e8 // velocity of space ship away from the earth in m/sec\n",
+"v1 = 2.1e8 // velocity of rocket w.r.t. space ship away from the earth in first case in m/sec\n",
+"v2 = -2.1e8 // velocity of rocket w.r.t. space ship away from the earth in second case in m/sec\n",
+"// Sample Problem 24 on page no. 11.27\n",
+"printf('\n # PROBLEM 24 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' u_x = u_x_ + v / (1+ v*u_x_/c^2) \n ')\n",
+"u1 = (v1 + v) / (1 + ((v1 * v) / (3e8)^2))\n",
+"u2 = (v2 + v) / (1 + ((v2 * v) / (3e8)^2))\n",
+"printf('\n Velocity of rocket w.r.t. earth in first case = %f c away from the earth.\n Velocity of rocket w.r.t. earth in second case = %f c away from the earth ',u1/3e8,u2/3e8)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 11.25: Calculation_of_Length_as_it_appear_to_the_observer.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"l = 1 // length of the rod in meter\n",
+"v = 1.8e8 // speed of rod along its length in meter/sec\n",
+"// Sample Problem 25 on page no. 11.28\n",
+"printf('\n # PROBLEM 25 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' l = l_0/((1-v^2/c^2)^1/2)  \n')\n",
+"L = l * sqrt(1- (v / 3e8)^2)\n",
+"printf('\n Length as it appear to the observer is %f meter. ',L)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 11.26: Calculation_of_Length_as_it_appear_to_the_observer.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"l = 2 // length of the rod in meter\n",
+"v = 2.7e8 // speed of rod along its length in meter/sec\n",
+"// Sample Problem 26 on page no. 11.28\n",
+"printf('\n # PROBLEM 26 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' l = l_0/((1-v^2/c^2)^1/2)  \n')\n",
+"L = l * sqrt(1- (v / 3e8)^2)\n",
+"printf('\n Length as it appear to the observer is %f meter.',L)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 11.27: Calculation_of_Percentage_length_contraction.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"l = 100 // consider the length of the rod in meter\n",
+"v = 2.4e8 // speed of rod in meter/sec\n",
+"theta = %pi / 3 // direction of velocity of rod along its length in radian\n",
+"// Sample Problem 27 on page no. 11.28\n",
+"printf('\n # PROBLEM 27 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' l = l_0/((1-v^2/c^2)^1/2)  \n l^2 = l_x^2 + l_y^2 \n')\n",
+"Lx = l * cos(theta)\n",
+"Ly = l * sin(theta)\n",
+"L_x = Lx * sqrt(1 - (v / 3e8)^2)\n",
+"L_y = Ly \n",
+"L = sqrt(L_x^2 + L_y^2)\n",
+"p_l = ((l - L) / l) * 100 \n",
+"printf('\n Percentage length contraction is %f percent.',p_l)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 11.28: Calculation_of_Speed_of_the_rod_relative_to_observer.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"r = 0.5 // ratio of length of rod when it is in motion to the length of the rod when it is in rest \n",
+"// Sample Problem 28 on page no. 11.29\n",
+"printf('\n # PROBLEM 28 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' l = l_0/((1-v^2/c^2)^1/2)  \n')\n",
+"v = 3e8 * sqrt(1 - r^2)\n",
+"printf('\n Speed of the rod relative to observer is %f c.',v/3e8)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 11.29: Calculation_of_Length_of_the_rod_in_moving_frame_and_Orientation_of_the_rod.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"l = 5 // length of the rod in meter\n",
+"v = 1.8e8 // speed of rod in meter/sec\n",
+"theta = %pi / 6 // direction of velocity of rod along its length in radian\n",
+"// Sample Problem 29 on page no. 11.30\n",
+"printf('\n # PROBLEM 29 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' l = l_0/((1-v^2/c^2)^1/2)  \n l^2 = l_x^2 + l_y^2 \n')\n",
+"Lx = l * cos(theta)\n",
+"Ly = l * sin(theta)\n",
+"L_x = Lx * sqrt(1 - (v / 3e8)^2)\n",
+"L_y = Ly \n",
+"L = sqrt(L_x^2 + L_y^2)\n",
+"orientation = atan(L_y / L_x) * (180 / %pi)\n",
+"printf('\n Length of the rod in moving frame is %f meter.\n Orientation of the rod is %f degree.',L,orientation)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 11.30: Calculation_of_half_life_of_particle.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"T = 17.8e-9 // half-life of prticle at rest in sec\n",
+"v = 2.4e8 // speed of particle in meter/sec\n",
+"// Sample Problem 30 on page no. 11.30\n",
+"printf('\n # PROBLEM 30 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' t = t_0/((1-v^2/c^2)^1/2) \n')\n",
+"t = T / (sqrt(1 - (v / 3e8)^2))\n",
+"printf('\n New half-life of particle is %f nanosec.',t/1e-9)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 11.31: Calculation_of_Time_lost_per_day.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"T = 24 // no. of hours in a day\n",
+"v = 1e8 // speed of spaceship in meter/sec\n",
+"// Sample Problem 31 on page no. 11.30\n",
+"printf('\n # PROBLEM 31 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' t = t_0/((1-v^2/c^2)^1/2) \n')\n",
+"t = T * (sqrt(1 - (v / 3e8)^2))\n",
+"T_ = T - t\n",
+"m=(T_-1)*60\n",
+"s=(m-22)*60\n",
+"printf('\n Time lost per day is %d hours %d minute %d sec.',T_,m,s)\n",
+"//Answer in the book:1 hr 22 min 12 sec\n",
+"//Answer in the program:1.372583 e+00 hours"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 11.32: Calculation_of_Speed_of_rocket.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"T = 4 // no. of year when rocket is moving corresponding to one year \n",
+"// Sample Problem 32 on page no. 11.30\n",
+"printf('\n # PROBLEM 32 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' t = t_0/((1-v^2/c^2)^1/2) \n')\n",
+"v = 3e8 * sqrt(1 - (1 / T)^2)\n",
+"printf('\n Speed of rocket is %f c.',v/3e8)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 11.33: Calculation_of_Time_taken_by_the_rocket.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"d = 4 // distance of star from the earth in light years\n",
+"v = 3e8 * sqrt(0.9999) // speed of rocket in meter/sec\n",
+"// Sample Problem 33 on page no. 11.31\n",
+"printf('\n # PROBLEM 33 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' t = t_0/((1-v^2/c^2)^1/2) \n')\n",
+"t = (2 * d * 3e8) / v\n",
+"T_ = t * sqrt(1 - (v / 3e8)^2)\n",
+"printf('\n Time taken by the rocket is %f year.',T_)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 11.34: Calculation_of_Proper_life_time_of_particle.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"t = 2e-7 // life time of particle when it is moving in sec\n",
+"v = 2.8e8 // speed of particle in meter/sec\n",
+"// Sample Problem 34 on page no. 11.31\n",
+"printf('\n # PROBLEM 34 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' t = t_0/((1-v^2/c^2)^1/2) \n')\n",
+"T_ = t * sqrt(1 - (v / 3e8)^2)\n",
+"printf('\n Proper life time of particle is %e sec.',T_)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 11.35: EX11_35.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"v1 = 2.7e8 // velocity of first electron beam in meter/sec\n",
+"v2 = -2.7e8 // velocity of second electron beam in meter/sec\n",
+"// Sample Problem 35 on page no. 11.31\n",
+"printf('\n # PROBLEM 35 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' u_x = u_x_ + v / (1+ v*u_x_/c^2) \n ')\n",
+"u = v1 - v2\n",
+"u_ = (v1 - v2) / (1 - (v1 * v2) / (3e8)^2)\n",
+"printf('\n Velocity of electrons beam w.r.t. another electron beam according to Newtonian mechanics is %f c.\n Velocity of electrons beam measured by the observer moving with other electron beam = %f c.',u/3e8,u_/3e8)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 11.36: Calculation_of_Relative_velocity_of_photons.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"c = 3e8 // velocity of photon in meter/sec\n",
+"// Sample Problem 36 on page no. 11.32\n",
+"printf('\n # PROBLEM 36 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' u_x = u_x_ + v / (1+ v*u_x_/c^2) \n ')\n",
+"u = (c + c) / ( 1 + (c / 3e8)^2)\n",
+"printf('\n Relative velocity of photons is %e meter/sec.',u)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 11.37: Calculation_of_Relativistic_mass_of_proton.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"E = 900 // total relativistic energy of proton in Mev\n",
+"m = 1.63-27 // rest mass of proton in kg\n",
+"c = 3e8 // velocity of photon in meter/sec\n",
+"// Sample Problem 37 on page no. 11.32\n",
+"printf('\n # PROBLEM 37 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' E = m*c^2 \n ')\n",
+"m_ = (E * 1.6e-13) / (c)^2\n",
+"printf('\n Relativistic mass of proton is %e kg,\n Here relativistic mass is same as rest mass\n hence proton is at rest and speed and kinetic energy of proton will be zero',m_)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 11.38: Calculation_of_Fraction_of_total_energy_content.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"E = 5.4e6 // energy liberates during dynamite explosion in J/kg\n",
+"c = 3e8 // velocity of photon in meter/sec\n",
+"// Sample Problem 38 on page no. 11.32\n",
+"printf('\n # PROBLEM 38 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' E = m*c^2 \n ')\n",
+"E_ = 1 * c^2 // energy liberated by 1 kg content in J\n",
+"f = E / E_\n",
+"printf('\n Fraction of total energy content in it is %e per kg.',f)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 11.39: Calculation_of_Speed_of_the_electron.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"k = 1.02 // kinetic energy of electron in Mev\n",
+"E_ = 0.51 // rest mass energy of electron in Mev\n",
+"c = 3e8 // velocity of photon in meter/sec\n",
+"// Sample Problem 39 on page no. 11.32\n",
+"printf('\n # PROBLEM 39 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' E = KE + m*c^2 \n m = m_0/((1-v^2/c^2)^1/2) \n')\n",
+"E = k + E_\n",
+"v = c * sqrt(1 - (E_ / E)^2)\n",
+"printf('\n Speed of the electron is %e meter/sec.',v)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 11.40: Calculation_of_Rate_of_decrement_of_mass_of_the_sun.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"E = 1400 // solar energy receives by the earth in W/square meter\n",
+"d = 1.5e11 // distance between earth and the sun in meter\n",
+"c = 3e8 // velocity of photon in meter/sec\n",
+"// Sample Problem 40 on page no. 11.33\n",
+"printf('\n # PROBLEM 40 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' E = m*c^2 \n ')\n",
+"E_ = 4 * %pi * d^2 * E\n",
+"m = E_ / c^2\n",
+"printf('\n Rate of decrement of mass of the sun is %e kg/sec.',m)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 11.5: EX11_5.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"x = 100 // in meter\n",
+"y = 10 // in meter\n",
+"z = 5  // in meter\n",
+"t = 1e-4 // in sec\n",
+"// coordinates of point in frame F\n",
+"v = 2.7e8 // velocity of frame F_ w.r.t. frame F in m/sed\n",
+"c=3e8 // speed of light in m/sec\n",
+"// Sample Problem 5 on page no. 11.19\n",
+"printf('\n # PROBLEM 5 # \n')\n",
+"// according to Galilean transformation\n",
+"x__ = x-v*t\n",
+"y__=y\n",
+"z__=z\n",
+"t__=t\n",
+"// according to Lorentz transformation\n",
+"x_ = (x-v*t)/sqrt(1-(v/c)^2)\n",
+"y_=y\n",
+"z_=z\n",
+"t_=(t-(v*x/c^2))/sqrt(1-(v/c)^2)\n",
+"printf('\n Coordinate of the event in reference frame F_ using (a)Galilean transformation-x=%f m, y=%f m, z = %f m, t = %e sec. \n (b)Lorentz transformation-x=%f m,y =%f m, z = %f m, t=%e sec. ',x__,y__,z__,t__,x_,y_,z_,t_)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 11.6: Calculation_of_Speed_of_particle.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"r = 4 // ratio of mass of particle to the rest mass\n",
+"// Sample Problem 6 on page no. 11.20\n",
+"printf('\n # PROBLEM 6 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' m = m_0/((1-v^2/c^2)^1/2) \n ')\n",
+"v = 3e8 * sqrt(1 - (1 / r)^2)\n",
+"printf('\n Speed of particle is %e meter/sec.',v)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 11.7: Calculation_of_Speed_of_particle.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"r = 1.2 // ratio of mass of particle to the rest mass\n",
+"// Sample Problem 7 on page no. 11.20\n",
+"printf('\n # PROBLEM 7 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' m = m_0/((1-v^2/c^2)^1/2) \n ')\n",
+"v = 3e8 * sqrt(1 - (1 / r)^2)\n",
+"printf('\n Speed of particle is %f c.',v/3e8)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 11.9: Calculation_of_Speed_of_electron_and_Mass_of_electron.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"E = 2 // kinetic energy of electron in Mev\n",
+"// Sample Problem 9 on page no. 11.20\n",
+"printf('\n # PROBLEM 9 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' m = m_0/((1-v^2/c^2)^1/2) \n  KE = m*c^2 - m_0*c^2 \n')\n",
+"v = 3e8 * sqrt(1 - (1 / (1 + (1.6e-19 * 2e6) / (9.1e-31 * 3e8^2)))^2)\n",
+"m = (9.1e-31) / sqrt(1 - (v / 3e8)^2)\n",
+"printf('\n Speed of electron is %f c.\n Mass of electron is %e kg.',v/3e8,m)"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Engineering_Physics_by_H_K_Malik/12-APPLIED_NUCLEAR_PHYSICS.ipynb b/Engineering_Physics_by_H_K_Malik/12-APPLIED_NUCLEAR_PHYSICS.ipynb
new file mode 100644
index 0000000..fcf6c9e
--- /dev/null
+++ b/Engineering_Physics_by_H_K_Malik/12-APPLIED_NUCLEAR_PHYSICS.ipynb
@@ -0,0 +1,1280 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 12: APPLIED NUCLEAR PHYSICS"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.10: Calculation_of_Activity_of_sample.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"t = 2.7 // half-life of Au(198) in days\n",
+"m = 1e-6 // mass of sample in gm\n",
+"T = 8 * 86400 // time in seconds\n",
+"// Sample Problem 10 on page no. 12.35\n",
+"printf('\n # PROBLEM 10 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' lambda = 0.693 / t_1/2     (Decay constant) \n A =lambda*N    (Activity of sample) \n')\n",
+"lambda = 0.693 / (t * 86400)\n",
+"N = (m * 6.023e23) / 198 // by the formula (N = mass*Avogadro number/molar mass)\n",
+"A_ = lambda * N\n",
+"A = A_ * (1 / exp(lambda * T))\n",
+"printf('\n Activity of sample is %e decays/sec.',A)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.11: Calculation_of_Fraction_of_sample.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"n = 3 // no. of half lives\n",
+"// Sample Problem 11 on page no. 12.35\n",
+"printf('\n # PROBLEM 11 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' N = 2^(-n) ...... fraction after n half lives.\n')\n",
+"f = (1 / 2)^n\n",
+"printf('\n Fraction of sample left after %d half lives is %f . ',n,f)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.12: Calculation_of_Substance_remained_unchanged.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"t = 2 // life period of radioactive substance in years\n",
+"T = 4 // time in years\n",
+"m = 10 // mass of substance in mg\n",
+"// Sample Problem 12 on page no. 12.35\n",
+"printf('\n # PROBLEM 12 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' N = N_0/2^(n) ...... fraction after n half lives.\n')\n",
+"N = m / T // in mg\n",
+"printf('\n  Substance remained unchanged after 4 years is %f mg.',N)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.13: Calculation_of_Decay_constant.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"m = 1 // initial mass of radium in gm\n",
+"m_ = 0.0021 // final mass of radium in gm\n",
+"t = 5 // time for decay from m to m_ in years\n",
+"// Sample Problem 13 on page no. 12.36\n",
+"printf('\n # PROBLEM 13 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' lambda = 0.693 / t_1/2     (Decay constant) \n N =N_0*e^(-lambda*t) \n')\n",
+"lambda = log(m / (1 - m_)) / t\n",
+"T = 0.693 / lambda\n",
+"T_ = 1 / lambda\n",
+"printf('\n Decay constant is %f per year.\n Half life of sample is %f years.\n Average life of sample is %f years.',lambda,T,T_)\n",
+"//Answer in the book:2500 years\n",
+"//Answer in the program:2378.451405 years"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.14: Calculation_of_Half_life_of_sample.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"t = 10 // time in days\n",
+"r = 15 // percentage fraction of sample which remain \n",
+"// Sample Problem 14 on page no. 12.36\n",
+"printf('\n # PROBLEM 14 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' lambda = 0.693 / t_1/2     (Decay constant) \n N =N_0*e^(-lambda*t) \n')\n",
+"lambda = log(100 / 15) / t\n",
+"T = 0.693 / lambda\n",
+"printf('\n Half life of sample is %f days.',T)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.15: Calculation_of_Fraction_of_radioactive_isotope_remained.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"t = 12.3 // half life in year\n",
+"T = 50 // time in year \n",
+"// Sample Problem 15 on page no. 12.36\n",
+"printf('\n # PROBLEM 15 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' lambda = 0.693 / t_1/2     (Decay constant) \n N =N_0*e^(-lambda*t) \n')\n",
+"lambda = 0.693 / t\n",
+"f = 1 / exp(lambda * T)\n",
+"printf('\n Fraction of radioactive isotope remained is %f .',f)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.16: Calculation_of_Mass_of_Pb.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"R = 1 // radioactivity of Pb(214) in curie\n",
+"t = 26.8 // half life in minute \n",
+"// Sample Problem 16 on page no. 12.37\n",
+"printf('\n # PROBLEM 16 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' lambda = 0.693 / t_1/2     (Decay constant) \n A =N*lambda      (Activity of sample) \n')\n",
+"lambda = 0.693 / (t * 60)\n",
+"R = 1 * 3.7e10 // in disintegration per sec\n",
+"m = (R * 214) / (6.023e23 * lambda)\n",
+"printf('\n Mass of Pb(214)is %e gm.',m)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.17: Calculation_of_Mass_of_Pb.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"R = 1e6 // radioactivity of Pb(214) in disintegrations per sec\n",
+"t = 26.8 // half life in minute \n",
+"// Sample Problem 17 on page no. 12.37\n",
+"printf('\n # PROBLEM 17 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' lambda = 0.693 / t_1/2     (Decay constant) \n A =N*lambda      (Activity of sample) \n')\n",
+"lambda = 0.693 / (t * 60)\n",
+"m = (R * 214) / (6.023e23 * lambda)\n",
+"printf('\n Mass of Pb(214) is %e gm.',m)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.18: Calculation_of_Mean_life_of_radium_and_Half_life_of_radium.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"m = 1 // mass of Ra(226) in gm \n",
+"R = 1 // radioactivity of Ra(226) in curie\n",
+"// Sample Problem 18 on page no. 12.37\n",
+"printf('\n # PROBLEM 18 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' lambda = 0.693 / t_1/2     (Decay constant) \n tau = 1/lambda \n A =N*lambda      (Activity of sample) \n')\n",
+"r = R * 3.7e10 // in disintegrations per sec\n",
+"N = 6.023e23 * m / 226\n",
+"lambda = r * 226 / 6.023e23\n",
+"T = 1 / lambda\n",
+"T_ = 0.693 / lambda\n",
+"printf('\n Mean life of radium is %e year.\n Half life of radium is %e year.',T,T_)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.19: Calculation_of_Activity_of_Sr.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"m = 0.0001 // mass of Sr(90) in gm\n",
+"t = 28 // half life of Sr(90) in year\n",
+"t_ = 9 // time in sec\n",
+"// Sample Problem 19 on page no. 12.38\n",
+"printf('\n # PROBLEM 19 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' lambda = 0.693 / t_1/2     (Decay constant) \n del_N = N_0*lambda*t (disintegration of sample) \n')\n",
+"lambda = 0.693 / (t * 86400 * 365)\n",
+"N_ = 6.023e23 * m / 90\n",
+"n = N_ * lambda * t_\n",
+"printf('\n Activity of Sr is %e disintegration/sec.',n)\n",
+"//Answer in the book:5.25 X 10^8\n",
+"//Answer in the program:4.726955 e+09"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.1: Calculation_of_Mass_absorption_coefficient_of_Al_and_Half_value_thickness.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"E = 1.14 // energy of gamma radiation in Mev\n",
+"l = 0.2 // length of aluminium in meter\n",
+"p = 0.03 // reduce in intensity in beam\n",
+"d = 2700 // density of aluminium in kg/m^3 \n",
+"// Sample Problem 1 on page no. 12.31\n",
+"printf('\n # PROBLEM 1 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf('I = I_0*e^(-mu*x) \n')\n",
+"mu = (1 / l) * log(1 / p)\n",
+"k = mu / d\n",
+"x = 0.693 / mu\n",
+"printf('\n Mass absorption coeffiecient of Al for this radiation is %f m^2/kg.\n Half value thickness is %f meter.',k,x)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.20: Calculation_of_Mass_of_radon.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"t = 1600 // the half life of radium(226) in year\n",
+"t1 = 3.8 // the half life of radon(222) in days\n",
+"m = 1 // mass of Ra(226) in gm\n",
+"// Sample Problem 20 on page no. 12.38\n",
+"printf('\n # PROBLEM 20 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' N_1*lambda_1 = N_2*lambda_2 \n')\n",
+"m_ = (222 * t1 * m) / (226 * 365 * t) // by the formula N1*t = N2*t1\n",
+"printf('\n Mass of radon is %e gm.',m_)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.21: Calculation_of_Energy_of_gamma_ray_photon.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"m1 = 4.002603 // mass of He(4) in a.m.u.\n",
+"m2 = 3.016056 // mass of H(3) in a.m.u.\n",
+"m3 = 1.007276 // mass of H(1) in a.m.u.\n",
+"// Sample Problem 21 on page no. 12.39\n",
+"printf('\n # PROBLEM 21 # \n')\n",
+"printf('Standard law used \n')\n",
+"printf(' Law of conservation of Energy \n')\n",
+"k = m2 + m3 - m1\n",
+"E = k * 931\n",
+"printf('\n Energy of gamma ray photon is %f MeV.',E)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.22: Calculation_of_Q_value_of_reaction.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"E = 3 // kinetic energy of proton in Mev\n",
+"m1 = 1.007276 // mass of H(1) in a.m.u.\n",
+"m2 = 3.016056 // mass of H(3) in a.m.u.\n",
+"m3 = 1.008665 // mass of neutron in a.m.u.\n",
+"m4 = 3.016036 // mass of He(3) in a.m.u.\n",
+"// Sample Problem 22 on page no. 12.39\n",
+"printf('\n # PROBLEM 22 # \n')\n",
+"printf('Standard law used \n')\n",
+"printf(' Law of conservation of Energy \n')\n",
+"k = m1 + m2 - m3 - m4\n",
+"E = k * 931.5\n",
+"printf('\n Q value of reaction is %f MeV.',E)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.23: Calculation_of_Heat_produce_by_complete_disintegration_and_Energy_released.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"E = 200 // energy released per fission in Mev\n",
+"m = 0.01 // mass of U(235) in gm\n",
+"n = 235 // atomic no of sample\n",
+"N_0=6.023e23 // Avogadro constant\n",
+"// Sample Problem 23 on page no. 12.40\n",
+"printf('\n # PROBLEM 23 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' E_total = E*N_0/n \n')\n",
+"E_ = E * 1.6e-13\n",
+"k = E_ * N_0 * m / n\n",
+"H = k / 4.168\n",
+"printf('\n Heat produce by complete disintegration is %e cal.\n Energy released is %e J.',H,E_)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.24: Calculation_of_Energy_released_by_fission.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"E = 200 // energy released per fission in Mev\n",
+"m = 1 // mass of U(235) in kg\n",
+"// Sample Problem 24 on page no. 12.40\n",
+"printf('\n # PROBLEM 24 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' E_total = E*N_0/n \n')\n",
+"E_ = E * 1.6e-13\n",
+"k = E_ * 6.023e26 * m / 235\n",
+"printf('\n Energy released  by fission of 1 kg of U(235)is %e J.',k)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.25: Calculation_of_Amount_of_fuel_required.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"P = 1e9 // power required for enlighten the city in watt\n",
+"e = 30 // percentage efficiency of nuclear reactor\n",
+"E = 3.2e-11 // energy released per fission in J\n",
+"// Sample Problem 25 on page no. 12.40\n",
+"printf('\n # PROBLEM 25 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' E_total = E*N_0/n \n')\n",
+"E_ = E * 30 / 100\n",
+"N = P / E_\n",
+"N_ = N * 24 * 3600\n",
+"m = N_ * 235 / 6.023e26 \n",
+"printf('\n Amount of fuel required per day is %f kg.',m)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.26: Calculation_of_Power_output_of_reactor.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"E = 200 // energy released per fission of U(235)in Mev\n",
+"m = 3.7 // mass of U(235) consumed in a day in kg\n",
+"e = 20 // percentage efficiency of reactor\n",
+"// Sample Problem 26 on page no. 12.41\n",
+"printf('\n # PROBLEM 26 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' E_total = E*N_0/n \n')\n",
+"E_ = E * 1.6e-13\n",
+"N = m * 6.023e26 / 235\n",
+"H = E_ * e / 100\n",
+"k = H * N / (24 * 3600)\n",
+"printf('\n Power output of reactor is %f GW.',k * 1e-9)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.27: Calculation_of_Energy_produce_by_each_reaction.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"m1 = 4.00260 // mass of He(4) in a.m.u.\n",
+"m2 = 0.00055 // mass of electron in a.m.u.\n",
+"m3 = 12 // mass of C(12) in a.m.u.\n",
+"// Sample Problem 27 on page no. 12.40\n",
+"printf('\n # PROBLEM 27 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' del_E = del_m * c^2 \n')\n",
+"delta_m = 3 * m1 - m3\n",
+"E = delta_m * 931\n",
+"printf('\n Energy produce by each reaction is %f MeV.',E)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.28: Calculation_of_Mass_of_deuterium.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"P = 5e7 // power in watt\n",
+"e = 33 // percentage efficiency of nuclear reactor\n",
+"m1 = 2.01478 // mass of H(2) in a.m.u.\n",
+"m2 = 4.00388 // mass of He(4) in a.m.u.\n",
+"// Sample Problem 28 on page no. 12.42\n",
+"printf('\n # PROBLEM 28 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' del_E = del_m * c^2 \n efficiency = output/input \n')\n",
+"m = (2 * m1) - m2\n",
+"E = m * 931 * 1.6e-13\n",
+"E_O = E * e /(2 * 100)\n",
+"N = P / E_O\n",
+"k = N * m1 / 6.023e26\n",
+"M = k * 24 * 3600 \n",
+"printf('\n Mass of deuterium consumed per day is %f kg.',M)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.29: Calculation_of_Number_of_revolution.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"d = 1.8 // diameter in meter\n",
+"B = 0.8 // magnetic field in tesla\n",
+"m = 6.68e-27 // mass of He(4) in kg\n",
+"e = 1.6e-19 // charge on an electron in Coulomb\n",
+"// Sample Problem 29on page no. 12.43\n",
+"printf('\n # PROBLEM 29 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' E = B^2*q^2*r^2/(2*m) \n f = B*q/(2*pi*m) \n')\n",
+"r = d / 2\n",
+"E = (B^2 * (2 * e)^2 * r^2) / (2 * m * 1.6e-19 * 10^6) \n",
+"f = B * 2 * e / (2 * %pi * m)\n",
+"N = f / 2\n",
+"printf('\n Energy  is %f MeV.\n Number of revolution made by particle to obtain above energy is %e per sec',E,N)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.2: Calculation_of_Mass_attenuation_coefficient_of_Al.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"E = 1.1 // energy of gamma radiation in Mev\n",
+"l = 0.25 // length of aluminium in meter\n",
+"p = 0.02 // reduce in intensity in beam\n",
+"d = 2700 // density of aluminium in kg/m^3 \n",
+"// Sample Problem 2 on page no. 12.32\n",
+"printf('\n # PROBLEM 2 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf('I = I_0*e^(-mu*x) \n')\n",
+"mu = (1 / l) * log(1 / p)\n",
+"k = mu / d\n",
+"x = 0.693 / mu\n",
+"printf('\n Mass attenuation coefficient of Al for this radiation is %e m^2/kg.\n Half value thickness is %f meter.',k,x)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.30: Calculation_of_Value_of_magnetic_induction_needed_to_accelerate_deuteron.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"f = 12e6 // oscillator frequency of cyclotron in Hz\n",
+"r = 0.53 // radius of dee in meter\n",
+"e = 1.6e-19 // charge on an electron in Coulomb\n",
+"// Sample Problem 30 on page no. 12.43\n",
+"printf('\n # PROBLEM 30 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' f = B*q/(2*pi*m) \n')\n",
+"B = (2 * %pi * f * 2 * 1.67e-27) / e\n",
+"printf('\n Value of magnetic induction needed to accelerate deuteron in it is %f T.',B)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.31: EX12_31.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"f = 10e6 // frequency of applied Emf in Hz\n",
+"r = 0.32 // radius in meter\n",
+"m = 3.32e-27 // mass of deuteron in kg\n",
+"e = 1.6e-19 // charge on an electron in Coulomb\n",
+"// Sample Problem 31 on page no. 12.44\n",
+"printf('\n # PROBLEM 31 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' q*v*B = m*v^2/r \n f = B*q/(2*pi*m) \n')\n",
+"B = (2 * %pi * f * m) / e\n",
+"v = (e * B * r) / m\n",
+"printf('\n Flux density of the magnetic field is %f T.\n Velocity of the deuterons emerging out of the cyclotron is %e m/sec. ',B, v)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.32: Calculation_of_Energy_gained_per_turn_and_Final_energy.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"f = 60 // operating frequency in Hz\n",
+"d = 1.6 // diameter in meter\n",
+"B = 0.5 // magnetic field at the orbit in tesla\n",
+"e = 1.6e-19 // charge on an electron in Coulomb\n",
+"// Sample Problem 32 on page no. 12.44\n",
+"printf('\n # PROBLEM 32 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' E_ = 3e8 * r * B / 1e6 \n')\n",
+"r = d / 2\n",
+"w = 2 * %pi * f\n",
+"E = 4 * e * w * r^2 * B\n",
+"E_ = 3e8 * r * B / 1e6\n",
+"printf('\n Energy gained per turn is %f eV.\n Final energy is %d MeV.',E / e,E_)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.33: Calculation_of_Magnitude_of_magnetic_field.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"E = 70 // energy of betatron synchrotron in Mev\n",
+"r = 0.28 // radius in meter\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"// Sample Problem 33 on page no. 12.45\n",
+"printf('\n # PROBLEM 33 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' E = c* e * r* B \n')\n",
+"E_ = E * 1.6e-13\n",
+"B = E_ / (3e8 * e * r)\n",
+"printf('\n Magnitude of magnetic field is %f T.',B)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.34: Calculation_of_The_current_produced.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"E = 4.18 // energy of alpha particle in Mev\n",
+"n = 12 // no. of particle enter the chamber per sec\n",
+"E_ = 40 // required energy of an ion pair in ev\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"// Sample Problem 34 on page no. 12.45\n",
+"printf('\n # PROBLEM 34 # \n')\n",
+"R = n * E * 10^6 // in eV\n",
+"N = R / E_\n",
+"i = N * e\n",
+"printf('Standard formula used \n N = R / E_.\n')\n",
+"printf('\n The current produced = %e Amp',i)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.35: Calculation_of_Average_current_in_the_circuit.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"n = 10^8 // no. of electron per discharge counted by GM counter\n",
+"r = 500 // counting rate in counts per minutes\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"// Sample Problem 35 on page no. 12.46\n",
+"printf('\n # PROBLEM 35 # \n')\n",
+"N = r / 60\n",
+"i = N * n * e \n",
+"printf('Standard formula used \n i = N * n * e . \n')\n",
+"printf('\n Average current in the circuit = %e Amp',i)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.36: Calculation_of_Frequency_of_cyclotron_and_Larmour_radius.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"E = 10 // energy of electron in kev\n",
+"B = 5e-5 // magnetic field of earth in tesla\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"// Sample Problem 36 on page no. 12.46\n",
+"printf('\n # PROBLEM 36 # \n')\n",
+"f = e * B / 9.1e-31\n",
+"E_ = E * 1.6e-16\n",
+"v = sqrt((2 * E_) / 9.1e-31)\n",
+"r = v / f\n",
+"printf('Standard formula used \n f = e * B / 9.1e-31 . \n')\n",
+"printf('\n Frequency of cyclotron = %e per sec,\n Larmour radius = %f meter',f,r)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.37: Calculation_of_Larmour_radius.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"B = 5e-9 // magnetic field in tesla\n",
+"v = 3e5 // velocity of proton stream in m/sec\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"// Sample Problem 37 on page no. 12.46\n",
+"printf('\n # PROBLEM 37 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' E = 1/2*m*v^2  \n')\n",
+"r = (1.67e-27 * v) / (e * B)\n",
+"printf('\n Larmour radius is %e meter.',r)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.38: Calculation_of_Magnetic_field.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"E = 1 // energy of He+ in kev\n",
+"r = 0.188 // Larmour radius in meter\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"// Sample Problem 38 on page no. 12.46\n",
+"printf('\n # PROBLEM 38 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' E = 1/2*m*v^2  \n E = q*B*v \n')\n",
+"E_ = E * 1.6e-16\n",
+"v = sqrt((2 * E_) / (4 * 1.67e-27))\n",
+"B = (4 * 1.67e-27 * v) / (e * r)\n",
+"printf('\n Magnetic field is %e tesla.',B)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.39: Calculation_of_Larmour_radius.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"E = 3.5 // energy of He++ ash particle in Mev\n",
+"B = 8 // magnetic field in tesla\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"// Sample Problem 39 on page no. 12.47\n",
+"printf('\n # PROBLEM 39 # \n')\n",
+"E_ = E * 1.6e-13\n",
+"v = sqrt(2 * E_ / (4 * 1.67e-27))\n",
+"printf(' Standard formula used \n')\n",
+"printf(' E = 1/2*m*v^2  \n E = q*B*v \n')\n",
+"r = (4 * 1.67e-27 * v) / (2 * e * B)\n",
+"printf('\n Larmour radius is %e meter.',r)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.3: Calculation_of_Time.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"t = 15 // half-life for Na(23) in hours\n",
+"r = 93.75 // percentage fraction of sample which decayed \n",
+"// Sample Problem 3 on page no. 12.32\n",
+"printf('\n # PROBLEM 3 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' lambda = 0.693 / t_1/2     (Decay constant) \n N =N_0*e^(-lambda*t) \n')\n",
+"lambda = 0.693 / t\n",
+"T = (1 / lambda) * (log(100 / (100 - r)))\n",
+"printf('\n Time taken for 93.75 per decay of sample is %d hours.',T)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.40: Calculation_of_Debye_length_and_Plasma_frequency.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"d = 1e12 // electron density in number per m^3\n",
+"E = 0.1 // thermal energy in eV\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"// Sample Problem 40 on page no. 12.47\n",
+"printf('\n # PROBLEM 40 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' l_debye = (epsilon_0*K*T/(n*e^2))^1/2  \n f = omega/(2*pi) \n')\n",
+"lambda = sqrt((8.85e-12 * E * e) / (d * e * e))\n",
+"omega = sqrt(d * e^2 / (9.1e-31 * 8.85e-12))\n",
+"f = omega / (2 * %pi)\n",
+"printf('\n Debye length is %e meter.\n Plasma frequency is %f MHz.',lambda,f / 1e6)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.41: Calculation_of_Debye_length_and_Plasma_frequency.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"d = 1e16 // density in per m^3\n",
+"E = 2 // thermal energy in eV\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"// Sample Problem 41 on page no. 12.48\n",
+"printf('\n # PROBLEM 41 # \n')\n",
+"lambda = sqrt((8.85e-12 * E * e) / (d * e * e))\n",
+"printf(' Standard formula used \n')\n",
+"printf(' l_debye = (epsilon_0*K*T/(n*e^2))^1/2  \n f = omega/(2*pi) \n')\n",
+"omega = sqrt(d * e^2 / (9.1e-31 * 8.85e-12))\n",
+"f = omega / (2 * %pi)\n",
+"printf('\n Debye length is %e meter.\n Plasma frequency is %e Hz.',lambda,f)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.4: Calculation_of_Time.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"t = 4 // half-life of radioactive element in years\n",
+"r = 1 / 64 // ratio of mass of element present in specimen to the initial mass of element \n",
+"// Sample Problem 4 on page no. 12.33\n",
+"printf('\n # PROBLEM 4 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' lambda = 0.693 / t_1/2     (Decay constant) \n N =N_0*e^(-lambda*t) \n')\n",
+"lambda = 0.693 / t\n",
+"T = (1 / lambda) * log(1 / r)\n",
+"printf('\n Time after which element present in specimen reduce to 1/64 of its original value is %d years.',T)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.5: Calculation_of_Period.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"t = 15 // half-life of radioactive element in years\n",
+"r = 0.025 // ratio of mass of element present in specimen to the intial mass of element \n",
+"// Sample Problem 5 on page no. 12.33\n",
+"printf('\n # PROBLEM 5 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' lambda = 0.693 / t_1/2     (Decay constant) \n N =N_0*e^(-lambda*t) \n')\n",
+"lambda = 0.693 / t\n",
+"T = (1 / lambda) * log(1 / r)\n",
+"printf('\n Period in which 2.5 percent of the initial quantity left over is %f years.',T)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.6: Calculation_of_Time.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"t = 3.8 // half-life for radon in days\n",
+"r = 60 // percentage fraction of sample which decayed \n",
+"// Sample Problem 6 on page no. 12.33\n",
+"printf('\n # PROBLEM 6 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' lambda = 0.693 / t_1/2     (Decay constant) \n N =N_0*e^(-lambda*t) \n')\n",
+"lambda = 0.693 / t\n",
+"T = (1 / lambda) * (log(100 / (100 - r)))\n",
+"printf('\n Time taken for 60 percent decay of sample is %f days.',T)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.7: Calculation_of_Half_life_time_and_Mean_life_time.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 4.28e-4 // decay constant in per year\n",
+"// Sample Problem 7 on page no. 12.34\n",
+"printf('\n # PROBLEM 7 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' lambda = 0.693 / t_1/2     (Decay constant) \n tau = 1/lambda \n')\n",
+"T = 0.693 / lambda\n",
+"t = 1 / lambda\n",
+"printf('\n Half life time is %f years.\n Mean life time is %f years.',T,t)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.8: Calculation_of_Half_life_of_radioactive_material.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"t = 30 // time in years\n",
+"r = 1 / 64 // ratio of final mass of element to the intial mass of element \n",
+"// Sample Problem 8 on page no. 12.34\n",
+"printf('\n # PROBLEM 8 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' lambda = 0.693 / t_1/2     (Decay constant) \n N =N_0*e^(-lambda*t) \n')\n",
+"lambda = log(1 / r) / t\n",
+"T = 0.693 / lambda\n",
+"printf('\n Half life of radioactive material is %d years.',ceil(T))"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 12.9: Calculation_of_Decay_constant.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"t = 2.1 // half life in minute\n",
+"r = 60 // percentage fraction of sample which decayed \n",
+"// Sample Problem 9 on page no. 12.34\n",
+"printf('\n # PROBLEM 9 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' lambda = 0.693 / t_1/2     (Decay constant) \n ')\n",
+"lambda = 0.693 / t\n",
+"printf('\n Decay constant is %f per minute.',lambda)"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Engineering_Physics_by_H_K_Malik/13-CRYSTAL_STRUCTURE.ipynb b/Engineering_Physics_by_H_K_Malik/13-CRYSTAL_STRUCTURE.ipynb
new file mode 100644
index 0000000..a346cdd
--- /dev/null
+++ b/Engineering_Physics_by_H_K_Malik/13-CRYSTAL_STRUCTURE.ipynb
@@ -0,0 +1,794 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 13: CRYSTAL STRUCTURE"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 13.10: Calculation_of_primitive_translation_vector.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"a = 3.56 // the length of cube edge in angstrom\n",
+"// Sample Problem 10 on page no. 13.28\n",
+"printf('\n # PROBLEM 10 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' d = a / sqrt(2) \n')\n",
+"d = a / sqrt(2)\n",
+"printf('\n Permitive translation vector is %f Angstrom.',d)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 13.11: Calculation_of_Number_of_atom_per_unit_cell.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"w = 207.2 // atomic weight of Pb\n",
+"d = 11.36e3 // density of Pb in kg/m^3\n",
+"a = 3.2e-10 // length of cube edge in meter\n",
+"N = 6.023e26 // Avogadro's no. in per kg mole\n",
+"// Sample Problem 11 on page no. 13.28\n",
+"printf('\n # PROBLEM 11 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' n = (a^3 * d * N) / w \n')\n",
+"n = (a^3 * d * N) / w\n",
+"printf('\n Number  of atom per unit cell is %d.',n)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 13.12: Calculation_of_Wavelength_of_x_ray.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"w = 60.2 // molecular weight\n",
+"d = 6250 // density in kg/m^3\n",
+"N = 6.023e+26 // Avogadro's no. in per kg mole\n",
+"n = 4 // for fcc lattice\n",
+"// Sample Problem 12 on page no. 13.28\n",
+"printf('\n # PROBLEM 12 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' a = (((4 * w) / (N * d))^(1 / 3)) \n')\n",
+"a = (((4 * w) / (N * d))^(1 / 3)) * 1e10\n",
+"printf('\n Lattice constant is %f angstrom.',a)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 13.13: Calculation_of_Wavelength_of_x_ray_and_Glancing_angle.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"x1 = 1 // coordinate on x axis of plane\n",
+"y1 = 0 // coordinate on y axis of plane\n",
+"z1 = 0 // coordinate on z axis of plane\n",
+"d = 2.82 // the space between successive plane in angstrom\n",
+"theta = 8.8 // glancing angle in degree\n",
+"// Sample Problem 13 on page no. 13.29\n",
+"printf('\n # PROBLEM 13 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' n*lambda = 2 * d * sin(theta) \n')\n",
+"n = 1\n",
+"lambda = 2 * d * sind(theta) / n\n",
+"printf('\n Wavelength of x-ray is %f angstrom.',lambda)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 13.14: Calculation_of_Lattice_constant_of_NaCl.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"d = 2.51 // the space between adjacent plane in angstrom\n",
+"theta = 9 // glancing angle in degree\n",
+"// Sample Problem 14 on page no. 13.29\n",
+"printf('\n # PROBLEM 14 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' n*lambda = 2 * d * sin(theta) \n')\n",
+"n = 1 // for n=1\n",
+"lambda = 2 * d * sind(theta) / n\n",
+"n = 2 // for n=2\n",
+"theta = asind(lambda / d)\n",
+"printf('\n Wavelength of x-ray is %f angstrom.\n Glancing angle for second order diffraction is %f degree.',lambda,theta)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 13.15: Calculation_of_Angle_of_incidence_of_x_ray_on_the_plane.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 1.5 // wavelength of x-ray in angstrom\n",
+"theta = 60 // glancing angle in degree\n",
+"// Sample Problem 15 on page no. 13.29\n",
+"printf('\n # PROBLEM 15 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' n*lambda = 2 * d * sin(theta) \n')\n",
+"n = 1 // for first order\n",
+"d = ( n * lambda) / (2 * sind(theta))\n",
+"printf('\n Lattice constant of NaCl is %f angstrom.',d)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 13.16: Calculation_of_Glancing_angle.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 1.4 // wavelength of x-ray in angstrom\n",
+"x1 = 1 // coordinate on x axis of plane\n",
+"y1 = 1 // coordinate on y axis of plane\n",
+"z1 = 1 // coordinate on z axis of plane\n",
+"a = 5 // lattice parameter of of crystal in angstrom\n",
+"// Sample Problem 16 on page no. 13.30\n",
+"printf('\n # PROBLEM 16 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' d = a / (x1^2 + y1^2 + z1^2)^1/2 \n')\n",
+"n = 1 // for first order\n",
+"d = a / sqrt(x1^2 + y1^2 + z1^2)\n",
+"theta = asind((n * lambda) / (2 * d))\n",
+"printf('\n Angle of incidence of x-ray on the plane is %f degree.',theta)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 13.17: Calculation_of_Wavelength_of_neutron_beam_and_Speed_of_neutron_beam.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 0.710 // wavelength of x-ray in angstrom\n",
+"x1 = 1 // coordinate on x axis of plane\n",
+"y1 = 0 // coordinate on y axis of plane\n",
+"z1 = 0 // coordinate on z axis of plane\n",
+"a = 2.814 // lattice parameter of of crystal in angstrom\n",
+"// Sample Problem 17 on page no. 13.30\n",
+"printf('\n # PROBLEM 17 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' n*lambda = 2 * d * sin(theta)\n')\n",
+"n = 2 // for second order\n",
+"d = a / sqrt(x1^2 + y1^2 + z1^2)\n",
+"theta = asind((n * lambda) / (2 * d))\n",
+"printf('\n Glancing angle is %f degree.',theta)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 13.18: Calculation_of_Lattice_parameter.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"n = 1 // order of brag reflection \n",
+"d = 3.84e-10 // the space between successive plane in m\n",
+"theta = 30 // glancing angle in degree\n",
+"// Sample Problem 18 on page no. 13.30\n",
+"printf('\n # PROBLEM 18 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' n*lambda = 2 * d * sin(theta) \n lambda = h/(m*v) \n')\n",
+"lambda = 2 * d * sind(theta) / n\n",
+"v = 6.62e-34 / (1.67e-27 * lambda)\n",
+"printf('\n Wavelength of neutron beam is %f angstrom.\n Speed of neutron beam is %e meter/sec.',lambda * 10^10,v)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 13.19: Calculation_of_Inter_planner_distances.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"v = 120 // voltage at which electron is accelerated in v\n",
+"n = 1 // order of Bragg reflection \n",
+"x1 = 1 // coordinate on x axis of plane\n",
+"y1 = 1 // coordinate on y axis of plane\n",
+"z1 = 1 // coordinate on z axis of plane\n",
+"theta = 22 // angle at which maximum reflection is obtain in degree\n",
+"n = 1 // order of reflection\n",
+"// Sample Problem 19 on page no. 13.31\n",
+"printf('\n # PROBLEM 19 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' n*lambda = 2 * d * sin(theta) \n lambda = h/(2*m*e*V)^1/2 \n')\n",
+"lambda = 6.62e-34 / sqrt(2 * 9.1e-31 * 1.6e-19 * v)\n",
+"d = (n * lambda) / (2 * sind(theta))\n",
+"a = d * sqrt(3) \n",
+"printf('\n Lattice parameter is %f angstrom.',a * 10^10)                           "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 13.1: Calculation_of_Miller_indices_of_the_plane.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"x = 2 // intercepts cut by the plane along vector a of crystallographic axes\n",
+"y = 3 // intercepts cut by the plane along vector b of crystallographic axes\n",
+"z = 1 // intercepts cut by the plane along vector c of crystallographic axes\n",
+"// Sample Problem 1 on page no. 13.24\n",
+"printf('\n # PROBLEM 1 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' x_ = a / x \n y_ = b / y \n z_ = c / z \n')\n",
+"x_ = 6 / x\n",
+"y_ = 6 / y\n",
+"z_ = 6 / z\n",
+"printf('\n Miller indices of the plane are (%d %d %d)',x_,y_,z_)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 13.20: Calculation_of_Inter_planner_distance.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 1.24e-10 // wavelength of X-ray in A\n",
+"x1 = 1 // coordinate on x axis of first plane\n",
+"y1 = 0 // coordinate on y axis of first plane\n",
+"z1 = 0 // coordinate on z axis of first plane\n",
+"x2 = 1 // coordinate on x axis of second plane\n",
+"y2 = 1 // coordinate on y axis of second plane\n",
+"z2 = 0 // coordinate on z axis of second plane\n",
+"x3 = 1 // coordinate on x axis of third plane\n",
+"y3 = 1 // coordinate on y axis of third plane\n",
+"z3 = 1 // coordinate on z axis of third plane\n",
+"M = 74.5 // molecular weight of KCl\n",
+"d = 1980 // density of KCl in kg/m^3\n",
+"N = 6.023e+26 // Avogadro's No per Kg mole\n",
+"// Sample Problem 20 on page no. 13.31\n",
+"printf('\n # PROBLEM 20 # \n')\n",
+"printf(' \n Standard formula used are D = 1/sqrt(x^2+y^2+z^2) and a^3 = n*M/(N*d)')\n",
+"a = (4*M / (N*d))^(1/3)\n",
+"D1 = a/sqrt(x1^2 + y1^2 + z1^2)\n",
+"D2 = a/sqrt(x2^2 + y2^2 + z2^2)\n",
+"D3 = a/sqrt(x3^2 + y3^2 + z3^2)\n",
+"printf('\n Inter planner distances are - \n (1) in first case %f A, \n (2) in second case %f A ,\n (3) in third case %f A',D1*10^10,D2*10^10,D3*10^10)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 13.21: Calculation_of_Potential_energy_of_molecule.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"d = 0.15e-9 // distance between K(+) and Cl(-) in m\n",
+"// Sample Problem 21 on page no. 13.32\n",
+"printf('\n # PROBLEM 21 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' v = -1.6e-19 / (4 * pi * 8.85e-12 * d) \n')\n",
+"v = -1.6e-19 / (4 * %pi * 8.85e-12 * d)\n",
+"printf('\n Potential energy of molecule is %f eV.',v)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 13.22: Calculation_of_Cohesive_energy_of_Nacl.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"d = 0.32e-9 // equilibrium separation in m\n",
+"alpha = 1.748 \n",
+"n = 9\n",
+"e = 4 // ionization energy in eV\n",
+"a = -2.16 // electron affinity in eV\n",
+"// Sample Problem 22 on page no. 13.32\n",
+"printf('\n # PROBLEM 22 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' E = -((alpha * 1.6e-19) / (4 * pi * 8.85e-12 * d)) * (1 - (1 / n)) \n')\n",
+"E = -((alpha * 1.6e-19) / (4 * %pi * 8.85e-12 * d)) * (1 - (1 / n))\n",
+"printf('\n Cohesive energy of Nacl is %f eV.',E)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 13.23: EX13_23.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"E = 2.02 // average energy required to produce a Schottky defect at room temperature in eV\n",
+"k = 1.38e-23 // Boltzmann constant in J/k\n",
+"T = 300 // room temperature in K\n",
+"// Sample Problem 23 on page no. 13.33\n",
+"printf('\n # PROBLEM 23 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' r = exp(-(E * 1.6e-19) / (2 * k * T))\n')\n",
+"r = exp(-(E * 1.6e-19) / (2 * k * T))\n",
+"printf('\n Ratio of number of Schottky defects to total number of cation-anion pairs is %e .',r)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 13.2: Calculation_of_Miller_indices_of_the_plane.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"x = 1 // intercepts cut by the plane along vector a of crystallographic axes\n",
+"y = 2 // intercepts cut by the plane along vector b of crystallographic axes\n",
+"z = -3 / 2 // intercepts cut by the plane along vector c of crystallographic axes\n",
+"// Sample Problem 2 on page no. 13.24\n",
+"printf('\n # PROBLEM 2 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' x_ = a / x \n y_ = b / y \n z_ = c / z \n')\n",
+"x_ = 6 / x\n",
+"y_ = 6 / y\n",
+"z_ = 6 / z\n",
+"printf('\n Miller indices of the plane are (%d %d %d)',x_,y_,z_)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 13.3: Calculation_of_Miller_indices_of_the_plane.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"x1 = 3 // intercepts cut by the plane along vector a of crystallographic axes in first case\n",
+"y1 = 3 // intercepts cut by the plane along vector b of crystallographic axes in first case \n",
+"z1 = 2 // intercepts cut by the plane along vector c of crystallographic axes in first case\n",
+"x2 = 1 // intercepts cut by the plane along vector a of crystallographic axes in second case\n",
+"y2 = 2 // intercepts cut by the plane along vector b of crystallographic axes in second case\n",
+"k2 = 0 // raciprocal of intercepts cut by the plane along vector c of crystallographic axes in second case\n",
+"x3 = 1 // intercepts cut by the plane along vector a of crystallographic axes in third case\n",
+"y3 = 1/2 // intercepts cut by the plane along vector b of crystallographic axes in third case\n",
+"z3 = 1 // intercepts cut by the plane along vector c of crystallographic axes in third case\n",
+"// Sample Problem 3 on page no. 13.24\n",
+"printf('\n # PROBLEM 3 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' x_ = a / x \n y_ = b / y \n z_ = c / z \n')\n",
+"x_1 = 6 / x1\n",
+"y_1 = 6 / y1\n",
+"z_1 = 6 / z1\n",
+"x_2 = 2 / x2\n",
+"y_2 = 2 / y2\n",
+"z_2 = 2*k2\n",
+"x_3 = 1 / x3\n",
+"y_3 = 1 / y3\n",
+"z_3 = 1 / z3\n",
+"printf('\n Miller indices of the plane (i) In first case are (%d %d %d),(ii) In second case are (%d %d %d),(iii)In the third case  are (%d %d %d).',x_1,y_1,z_1,x_2,y_2,z_2,x_3,y_3,z_3)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 13.4: Calculation_of_Spacing_between_the_plane.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"x1 = 1 // coordinate on x axis for first plane\n",
+"y1 = 0 // coordinate on y axis for first plane\n",
+"z1 = 0 // coordinate on z axis for first plane\n",
+"x2 = 1 // coordinate on x axis for second plane\n",
+"y2 = 1 // coordinate on y axis for second plane\n",
+"z2 = 1 // coordinate on z axis for second plane\n",
+"// Sample Problem 4 on page no. 13.25\n",
+"printf('\n # PROBLEM 4 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' d = 1 / (x1^2 + y1^2 + z1^2)^1/2 \n')\n",
+"d1 = 1 / sqrt(x1^2 + y1^2 + z1^2)\n",
+"d2 = 1 / sqrt(x2^2 + y2^2 + z2^2)\n",
+"printf('\n Spacing between the plane in first case is a / %d.\n Spacing between the plane in second case is a / %f .',d1,d2)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 13.5: Calculation_of_Miller_indices_of_the_plane_and_Inter_planer_distance.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"x = 1 // intercepts cut by the plane along vector a of crystallographic axes\n",
+"y = 2 // intercepts cut by the plane along vector b of crystallographic axes\n",
+"k = 0 // raciprocal of intercepts cut by the plane along vector c of crystallographic axes\n",
+"a = 5 // length of vector a of crystallographic axes in angstrom\n",
+"b = 5 // length of vector b of crystallographic axes in angstrom \n",
+"c = 5 // length of vector c of crystallographic axes in angstrom\n",
+"// Sample Problem 5 on page no. 13.26\n",
+"printf('\n # PROBLEM 5 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' d = 1 / (x1^2 + y1^2 + z1^2)^1/2 \n')\n",
+"x_ = 2 / x\n",
+"y_ = 2 / y\n",
+"z_ = 2 * k\n",
+"d = a / sqrt(x_^2 + y_^2 + z_^2)\n",
+"D=d^2\n",
+"printf('\n Miller indices of the plane are (%d %d %d).\n Inter planar distance is sqrt(%d) angstrom.',x_,y_,z_,D)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 13.6: Calculation_of_Miller_indices_of_the_plane.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"x = 2 // intercepts cut by the plane along vector a of crystallographic axes\n",
+"y = 2 / 3 // intercepts cut by the plane along vector b of crystallographic axes\n",
+"k = 0 // raciprocal of intercepts cut by the plane along vector c of crystallographic axes\n",
+"// Sample Problem 6 on page no. 13.26\n",
+"printf('\n # PROBLEM 6 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' x_ = a / x \n y_ = b / y \n z_ = c / z \n')\n",
+"x_ = 2 / x\n",
+"y_ = 2 / y\n",
+"z_ = 2 * k\n",
+"printf('\n Miller indices of the plane are (%d %d %d)',x_,y_,z_)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 13.7: Calculation_of_Miller_indices_of_the_plane.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"x1 = 2 // coordinate on x axis \n",
+"y1 = 3 // coordinate on y axis \n",
+"z1 = 1 // coordinate on z axis \n",
+"r = 0.175 // atomic radius of fcc structure in nm\n",
+"// Sample Problem 7 on page no. 13.27\n",
+"printf('\n # PROBLEM 7 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' d = 1 / (x1^2 + y1^2 + z1^2)^1/2 \n')\n",
+"a = (4 * r) / sqrt(2)\n",
+"d = a / sqrt(x1^2 + y1^2 + z1^2)\n",
+"printf('\n Inter planar spacing is %f nm.',d)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 13.8: Calculation_of_ratio_of_intercepts_and_The_ratio_of_spacing_between_two_planes.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"x1 = 1 // coordinate on x axis in first case\n",
+"y1 = 2 // coordinate on y axis in first case \n",
+"z1 = 3 // coordinate on z axis in first case\n",
+"x2 = 1\n",
+"y2 = 1\n",
+"z2 = 0\n",
+"// coordinate of first plane in second case\n",
+"x3 = 1\n",
+"y3= 1\n",
+"z3 = 1\n",
+"// coordinate of second plane in second case\n",
+"// Sample Problem 8 on page no. 13.27\n",
+"printf('\n # PROBLEM 8 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' d = 1 / (x1^2 + y1^2 + z1^2)^1/2 \n')\n",
+"x_=6/x1\n",
+"y_=6/y1\n",
+"z_=6/z1\n",
+"d1 = 1 / sqrt(x2^2 + y2^2 + z2^2)\n",
+"d2= 1/ sqrt(x3^2 + y3^2 + z3^2)\n",
+"d = d1/d2\n",
+"printf('\n The ratio of intercepts of three axes by the point are %d : %d : %d. \n The ratio of  spacing between two planes is %f.',x_,y_,z_,d)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 13.9: Calculation_of_Distance_between_two_atoms.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"a = 5 // the lattice constant of the structure in angstrom\n",
+"// Sample Problem 9 on page no. 13.28\n",
+"printf('\n # PROBLEM 9 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' d = a*sqrt(3) /4 \n')\n",
+"d = (sqrt(3) / 4) * a\n",
+"printf('\n Distance between two atoms is %f Angstrom. ',d)\n",
+"                                                               "
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Engineering_Physics_by_H_K_Malik/14-DEVELOPMENT_OF_QUANTUM_MECHANICS.ipynb b/Engineering_Physics_by_H_K_Malik/14-DEVELOPMENT_OF_QUANTUM_MECHANICS.ipynb
new file mode 100644
index 0000000..c4b7d79
--- /dev/null
+++ b/Engineering_Physics_by_H_K_Malik/14-DEVELOPMENT_OF_QUANTUM_MECHANICS.ipynb
@@ -0,0 +1,1557 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 14: DEVELOPMENT OF QUANTUM MECHANICS"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 1.1: Calculation_of_Frequency_and_Wavelength.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"E = 75 // energy of photon in eV\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"c = 3e8 // speed of light in m/sec\n",
+"e = 1.6e-19 // charge on an electron in J \n",
+"// Sample Problem 1 on page no. 14.20\n",
+"printf('\n # PROBLEM 1 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' E = h*c/lambda \n')\n",
+"f = E * e / h\n",
+"lambda = c / f \n",
+"printf('\n Frequency is %e Hz.\n Wavelength is %f Angstrom.',f,lambda * 10^10)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.10: Calculation_of_Maximum_energy_of_photoelectron.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"f = 1.2e15 // frequency of light in Hz\n",
+"f_ = 1.1e+15 // threshold frequency of photoelectron emission in copper in Hz\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"c = 3e8 // speed of light in m/sec\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"// Sample Problem 10 on page no. 14.23\n",
+"printf('\n # PROBLEM 10 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' 1/2 m*v^2 = h*(mu - mu_0) \n')\n",
+"E = h * (f - f_) / e\n",
+"printf('\n Maximum energy of photoelectron is %f eV.',E)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.11: Calculation_of_Work_function.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 6.2e-7 // threshold wavelength of photoelectron in first case in meter\n",
+"lambda_ = 5e-7 // threshold wavelength of photoelectron in second case in meter\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"c = 3e8 // speed of light in m/sec\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"// Sample Problem 11 on page no. 14.23\n",
+"printf('\n # PROBLEM 11 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' E = h*c/lambda \n')\n",
+"w = ((h * c) / lambda) * (1 / e)\n",
+"w_ = ((h * c) / lambda_) * (1 / e)\n",
+"printf('\n Work function for wavelength %e angstrom is %f eV.\n Work function for wavelength %e angstrom is %f eV',lambda,w,lambda_,w_)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.12: Calculation_of_Work_function_and_Maximum_energy_and_Threshold_frequency.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 3.132e-7 // wavelength of light in meter\n",
+"V = 1.98 // stopping potential in V\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"c = 3e8 // speed of light in m/sec\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"m = 9.1e-31 // mass of an electron in kg \n",
+"// Sample Problem 12 on page no. 14.24\n",
+"printf('\n # PROBLEM 12 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' 1/2 m*v^2 = h*(mu - mu_0) \n')\n",
+"E = e * V\n",
+"lambda_ = 1 / ((1 / lambda) - (E / (h * c)))\n",
+"f = c / lambda_\n",
+"w = ((h * c) / lambda_)\n",
+"printf('\n Work function is %e J.\n Maximum energy is %e J.\n Threshold frequency is %e Hz.',w,E,f)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.13: Calculation_of_work_function.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"w = 4.8 // work function in eV\n",
+"lambda1 = 5e-7 // wavelength of incident radiation in first case in meter\n",
+"lambda2 = 2e-7 // wavelength of incident radiation in second case in meter\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"c = 3e8 // speed of light in m/sec\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"// Sample Problem 13 on page no. 14.24\n",
+"printf('\n # PROBLEM 13 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' E_k = h*c/lambda \n')\n",
+"E_k1 = h*c/lambda1\n",
+"E_k2 = h*c / lambda2\n",
+"printf('\n From the above it is clear that the energy corresponding to wavelength 5000 A is i.e. %f found to be less than the work function i.e. 4.8 eV . So it will not be able to liberate an electron.\n As the energy to wavelength 2000 A i.e. %f is greater than the work function. So it is sufficient to liberate electrons. ',E_k1/e,E_k2/e)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.14: Calculation_of_Work_function_and_Maximum_energy_and_Threshold_frequency.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 5.893e-7 // wavelength of light in meter\n",
+"V = 0.36 // stopping potential for emitted electron in eV\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"c = 3e8 // speed of light in m/sec\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"m = 9.1e-31 // mass of an electron in kg \n",
+"// Sample Problem 14 on page no. 14.25\n",
+"printf('\n # PROBLEM 14 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' E_k = h*mu - phi \n')\n",
+"E = h * c / lambda\n",
+"w = ((h * c) / lambda) * (1 / e) - V\n",
+"f = w * e / h\n",
+"printf('\n Maximum energy is %f eV.\n Work function is %f eV.\n Threshold frequency is %e Hz. ',E/e,w,f)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.15: Calculation_of_Stopping_potential_and_Maximum_kinetic_energy.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 5.89e-7 // wavelength of light in meter\n",
+"lambda_ = 7.32e-7 // threshold wavelength of photoelectron in meter\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"c = 3e8 // speed of light in m/sec\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"m = 9.1e-31 // mass of an electron in kg \n",
+"// Sample Problem 15 on page no. 14.25\n",
+"printf('\n # PROBLEM 15 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' E = (h * c) * (1 / lambda1 - 1 / lambda2) \n')\n",
+"E = (h * c) * (1 / lambda - 1 / lambda_)\n",
+"V = E / e\n",
+"printf('\n Stopping potential is %f V.\n Maximum kinetic energy is %e J.',V,E)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.16: Calculation_of_Wavelength_of_light.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"E = 1.5 // maximum energy in eV\n",
+"lambda_ = 2.3e-7 // threshold wavelength of photoelectron in meter\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"c = 3e8 // speed of light in m/sec\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"m = 9.1e-31 // mass of an electron in kg \n",
+"// Sample Problem 16 on page no. 14.26\n",
+"printf('\n # PROBLEM 16 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' E = (h * c) * (1 / lambda1 - 1 / lambda2) \n')\n",
+"lambda = 1 / ((E * e / (h * c)) + (1 / lambda_))\n",
+"printf('\n Wavelength of light is %f Angstrom.',lambda * 1e10)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.17: EX14_17.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 1.5e-7 // wavelength of light in in meter\n",
+"w = 4.53 // work function of tungsten in eV\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"c = 3e8 // speed of light in m/sec\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"// Sample Problem 17 on page no. 14.26\n",
+"printf('\n # PROBLEM 17 # \n')\n",
+"printf(' Standard formula used \n ')\n",
+"printf(' E = (h * c)/lambda = 1/2*m*v^2 \n ')\n",
+"E = ((h * c) / lambda) * (1 / e)\n",
+"k = E - w\n",
+"printf('\n Energy of incident photon is %f eV,which is greater than the work function \n So it causes photoelectric emission.\n Kinetic energy of the emitted electron is %f eV.',E,k)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.18: Calculation_of_Longest_wavelength_required_for_photoemission.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"w = 2.3 // work function of sodium in eV\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"c = 3e8 // speed of light in m/sec\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"// Sample Problem 18 on page no. 14.26\n",
+"printf('\n # PROBLEM 18 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' E = (h * c)/ lambda \n')\n",
+"lambda = ((h * c) / w) * (1 / e)\n",
+"printf('\n Longest wavelength required for photoemission is %f Angstrom',lambda * 1e10)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.19: Calculation_of_Threshold_wavelength_for_photo_emission.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"w = 2 // work function of sodium in eV\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"c = 3e8 // speed of light in m/sec\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"// Sample Problem 19 on page no. 14.27\n",
+"printf('\n # PROBLEM 19 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' E = (h * c)/ lambda \n')\n",
+"lambda = ((h * c) / w) * (1 / e)\n",
+"printf('\n Threshold wavelength for photo emission is %d Angstrom.',lambda * 1e10)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.20: Calculation_of_Threshold_wavelength_and_Incident_electromagnetic_wavelength.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"k = 4 // maximum kinetic energy of electron in eV\n",
+"w = 2.2 // work function of sodium in eV\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"c = 3e8 // speed of light in m/sec\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"// Sample Problem 20 on page no. 14.27\n",
+"printf('\n # PROBLEM 20 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' E = (h * c) * (1 / lambda1 - 1 / lambda2) \n E = (h * c)/ lambda \n')\n",
+"lambda_ = ((h * c) / (w * e)) \n",
+"lambda = (1 / ((((k * e)  / (h * c))) + (1 / lambda_)))\n",
+"printf('\n Threshold wavelength is %d Angstrom.\n Incident electromagnetic wavelength is %f Angstrom',lambda_ * 1e10,lambda * 1e10)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.21: Calculation_of_Maximum_kinetic_energy_and_Number_of_electrons_emitted_per_sec.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 3.5e-7 // wavelength of light in meter\n",
+"i = 1 // intensity in W/m^2\n",
+"p = 0.5 // percent of incident photon produce electron\n",
+"a = 1 // surface area of potassium in cm^2\n",
+"w = 2.1 // work function of potassium in eV\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"c = 3e8 // speed of light in m/sec\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"m = 9.1e-31 // mass of an electron in kg \n",
+"// Sample Problem 21 on page no. 14.28\n",
+"printf('\n # PROBLEM 21 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' 1/2*m*v^2 = (h * c)/ lambda\n')\n",
+"E = (((h * c) / lambda) * (1 / e) - w) * e\n",
+"E_ = (p * a * 1e-4) / 100 // in W/cm^2\n",
+"n = E_ / E\n",
+"printf('\n Maximum kinetic energy is %e J.\n Number of electrons emitted per sec from 1cm^2 area is %e .',E,n)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.22: Calculation_of_Value_of_Planck_constant.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 5.896e-7 // wavelength of first light in meter\n",
+"lambda_ = 2.83e-7 // wavelength of second light in meter\n",
+"V1 = 0.12 // stopping potential for emitted electrons for first light in V\n",
+"V2 = 2.2 // stopping potential for emitted electrons for second light in V\n",
+"c = 3e8 // speed of light in m/sec\n",
+"e = 1.6e-19 // charge on an electron in C \n",
+"// Sample Problem 22 on page no. 14.28\n",
+"printf('\n # PROBLEM 22 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' E = (h * c) * (1 / lambda1 - 1 / lambda2)  \n')\n",
+"h = (e * (V2 - V1) / c) / (1 / lambda_ - 1 / lambda)\n",
+"printf('\n Value of Planck constant is %e J-sec.',h)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.23: Calculation_of_Compton_shift.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 1e-10 // wavelength of light in meter\n",
+"theta = 90 // angle at which scattered radiation is viewed in degree\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"c = 3e8 // speed of light in m/sec\n",
+"e = 1.6e-19 // charge on an electron in C \n",
+"m = 9.1e-31 // mass of an electron in kg\n",
+"// Sample Problem 23 on page no. 14.29\n",
+"printf('\n # PROBLEM 23 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' delta_lambda = (h / (m * c) * (1 - cos(theta))) \n')\n",
+"delta_lambda = (h * (1 - cosd(theta))) / (m * c)\n",
+"printf('\n Compton shift is %f Angstrom',delta_lambda * 1e10)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.24: Calculation_of_Compton_shift_and_Energy_of_incident_beam.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 1e-10 // wavelength of light in meter\n",
+"theta = 90 // angle in degree\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"c = 3e8 // speed of light in m/sec\n",
+"e = 1.6e-19 // charge on an electron in C \n",
+"m = 9.1e-31 // mass of an electron in kg\n",
+"// Sample Problem 24 on page no. 14.29\n",
+"printf('\n # PROBLEM 24 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' delta_lambda = (h / (m * c) * (1 - cos(theta))) \n')\n",
+"delta_lambda = (h * (1 - cosd(theta))) / (m * c)\n",
+"E = (h * c) / delta_lambda\n",
+"printf('\n Compton shift is %f Angstrom.\n Energy of incident beam is %f MeV.',delta_lambda * 1e10,E / 1.6e-13)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.25: Calculation_of_Wavelength_of_incident_beam.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"E = 4 // enrgy of recoil electron in KeV\n",
+"theta = 180 // scattered angle of photon in degree\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"c = 3e8 // speed of light in m/sec\n",
+"e = 1.6e-19 // charge on an electron in C \n",
+"m = 9.1e-31 // mass of an electron in kg\n",
+"// Sample Problem 25 on page no. 14.30\n",
+"printf('\n # PROBLEM 25 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' 1/2*m*v^2 = h*c*(1/lambda1 - 1/lambda2)\n')\n",
+"p = sqrt(2 * E * 10^3 * e * m)\n",
+"lambda = (2 * h * c) / (p * c + E * 10^3 * e)\n",
+"printf('\n Wavelength of incident beam is %f Angstrom.',lambda * 1e10)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.26: Calculation_of_Compton_shift_and_Kinetic_energy.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 1e-10 // wavelength of light in meter\n",
+"theta = 90 // angle in degree\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"c = 3e8 // speed of light in m/sec\n",
+"e = 1.6e-19 // charge on an electron in C \n",
+"m = 9.1e-31 // mass of an electron in kg\n",
+"// Sample Problem 26 on page no. 14.31\n",
+"printf('\n # PROBLEM 26 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' delta_lambda = (h / (m * c) * (1 - cos(theta))) \n E = h*c*(1/lambda1 - 1/lambda2)\n')\n",
+"delta_lambda = (h * (1 - cosd(theta))) / (m * c)\n",
+"E = (h * c) * ((1 / lambda) - (1 / (lambda + delta_lambda)))\n",
+"printf('\n Compton shift is %e m.\n Kinetic energy is %f eV.',delta_lambda,E / 1.6e-19)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.27: Calculation_of_Maximum_Compton_shift_and_Kinetic_energy.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 0.144e-10 // wavelength of x-ray in meter\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"c = 3e8 // speed of light in m/sec\n",
+"e = 1.6e-19 // charge on an electron in C \n",
+"m = 9.1e-31 // mass of an electron in kg\n",
+"// Sample Problem 27 on page no. 14.31\n",
+"printf('\n # PROBLEM 27 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' delta_lambda = (h / (m * c) * (1 - cos(theta))) \n E = h*c*(1/lambda1 - 1/lambda2)\n')\n",
+"theta = 180 // for maximum shift\n",
+"delta_lambda = (h * (1 - cosd(theta))) / (m * c)\n",
+"E = (h * c) * ((1 / lambda) - (1 / (lambda + delta_lambda)))\n",
+"printf('\n Maximum Compton shift is %f A.\n Kinetic energy is %f KeV.',delta_lambda * 1e10,E / 1.6e-16)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.28: Calculation_of_Wavelength_of_x_ray_and_Maximum_kinetic_energy.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 0.2e-10 // wavelength of x-ray in meter\n",
+"theta = 45 // scattered angle in degree\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"c = 3e8 // speed of light in m/sec\n",
+"e = 1.6e-19 // charge on an electron in C \n",
+"m = 9.1e-31 // mass of an electron in kg\n",
+"// Sample Problem 28 on page no. 14.32\n",
+"printf('\n # PROBLEM 28 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' delta_lambda = (h / (m * c) * (1 - cos(theta))) \n E = h*c*(1/lambda1 - 1/lambda2)\n')\n",
+"delta_lambda = (h * (1 - cosd(theta))) / (m * c)\n",
+"E = (h * c) * ((1 / lambda) - (1 / (lambda + delta_lambda)))\n",
+"theta_ = 180 // for maximum\n",
+"delta_lambda_ = (h * (1 - cosd(theta_))) / (m * c)\n",
+"lambda_ = lambda + delta_lambda_\n",
+"E_k = h*c*(1/lambda - 1/lambda_)\n",
+"printf('\n Wavelength of x-ray is %f A.\n Maximum kinetic energy %e J.',lambda_ * 1e10,E_k)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.29: Calculation_of_deBroglie_wavelength.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"v = 96 // speed of automobile in km/hr\n",
+"e = 1.6e-19 // charge on an electron in C \n",
+"m = 2e3 // mass of automobile in kg\n",
+"// Sample Problem 29 on page no. 14.33\n",
+"printf('\n # PROBLEM 29 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' lambda = h /(m*v)\n')\n",
+"v_ = v * (5 / 18)\n",
+"lambda = h / (m * v_)\n",
+"printf('\n de-Broglie wavelength is %e m.',lambda)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.2: Calculation_of_Number_of_quanta.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"P = 2e5 // radiated power in W\n",
+"f = 98e6 // frequency in Hz \n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"c = 3e8 // speed of light in m/sec\n",
+"e = 1.6e-19 // charge on an electron in C \n",
+"// Sample Problem 2 on page no. 14.20\n",
+"printf('\n # PROBLEM 2 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' E = h*mu \n')\n",
+"E = h * f\n",
+"n = P / E\n",
+"printf('\n Number of quanta emitted per sec is %e . ',n)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.30: Calculation_of_deBroglie_wavelength.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"v = 50 // potential differece in volt\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"c = 3e8 // speed of light in m/sec\n",
+"e = 1.6e-19 // charge on an electron in C \n",
+"m = 9.1e-31 // mass of an electron in kg\n",
+"// Sample Problem 30 on page no. 14.33\n",
+"printf('\n # PROBLEM 30 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' lambda = h /(m*v)\n 1/2*m*v^2 = eV \n')\n",
+"lambda =  h  / sqrt(2 * m * v * e)\n",
+"printf('\n de-Broglie wavelength is %f Angstrom.',lambda * 1e10)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.31: Calculation_of_Wavelength_of_thermal_neutron.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"t = 300 // temperature in K\n",
+"k = 1.37e-23 // Boltzmann's constant in J/K\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"e = 1.6e-19 // charge on an electron in C \n",
+"m = 1.67e-27 // mass of neutron in kg\n",
+"// Sample Problem 31 on page no. 14.33\n",
+"printf('\n # PROBLEM 31 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' lambda = h /(m*v)\n 1/2*m*v^2 = 3/2*k*T \n')\n",
+"lambda = h / sqrt(3 * m * k * t)\n",
+"printf('\n Wavelength of thermal neutron is %f Angstrom.',lambda * 1e10)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.32: Calculation_of_Wavelength_of_matter_wave.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"v = 2e8 // speed of proton in m/sec\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"e = 1.6e-19 // charge on an electron in C \n",
+"m = 1.67e-27 // mass of proton in kg\n",
+"// Sample Problem 32 on page no. 14.34\n",
+"printf('\n # PROBLEM 32 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' lambda = h /(m*v) \n')\n",
+"lambda = h / (m * v)\n",
+"printf('\n Wavelength of matter wave associated with proton is %e m',lambda)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.33: Calculation_of_Potential_difference.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 0.1e-10 // DE Broglie wavelength associated with electron in M\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"e = 1.6e-19 // charge on an electron in C \n",
+"m = 9.1e-31 // mass of electron in kg\n",
+"// Sample Problem 33 on page no. 14.34\n",
+"printf('\n # PROBLEM 33 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' lambda = h /(m*v)\n 1/2*m*v^2 = qV \n')\n",
+"V = h^2 / (2 * m* e * lambda^2)\n",
+"printf('\n Potential difference is %f KV.',V * 10^-3)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.34: Calculation_of_deBroglie_wavelength.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"v = 200 // potential differece in volt\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"c = 3e8 // speed of light in m/sec\n",
+"q = 3.2e-19 // charge on an alpha particle in C \n",
+"m = 4 * 1.67e-27 // mass of alpha particle in kg\n",
+"// Sample Problem 34 on page no. 14.34\n",
+"printf('\n # PROBLEM 34 # \n')\n",
+"printf('Standerd formula used \n ')\n",
+"printf(' lambda = h /(m*v)\n 1/2*m*v^2 = qV \n')\n",
+"lambda =  h  / sqrt(2 * m * v * q)\n",
+"printf('\n de-Broglie wavelength = %e m.',lambda)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.35: Calculation_of_deBroglie_wavelength.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"t = 400 // temperature in K\n",
+"k = 1.38e-23 // Boltzmann's constant in J/K\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"e = 1.6e-19 // charge on an electron in C \n",
+"m = 4 * 1.67e-27 // mass of helium atom in kg\n",
+"// Sample Problem 35 on page no. 14.34\n",
+"printf('\n # PROBLEM 35 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' lambda = h /(m*v)\n 1/2*m*v^2 = 3/2*k*T \n')\n",
+"lambda = h / sqrt(3 * m * k * t)\n",
+"printf('\n de-Broglie wavelength = %f Angstrom.',lambda * 1e10)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.36: Calculation_of_deBroglie_wavelength.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"v = 2000 // velocity of neutron in m/sec\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"e = 1.6e-19 // charge on an electron in C \n",
+"m = 1.67e-27 // mass of neutron in kg\n",
+"// Sample Problem 36 on page no. 14.35\n",
+"printf('\n # PROBLEM 36 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' lambda = h /(m*v)\n')\n",
+"lambda = h / (m * v)\n",
+"printf('\n de-Broglie wavelength is %f Angstrom.',lambda * 1e10)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.37: Calculation_of_Energy.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 1e-10 // wavelength in m\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"e = 1.6e-19 // charge on an electron in C \n",
+"m = 9.1e-31 // mass of electron in kg\n",
+"m_ = 1.67e-27 // mass of neutron in kg\n",
+"// Sample Problem 37 on page no. 14.35\n",
+"printf('\n # PROBLEM 37 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' lambda = h /(m*v)\n')\n",
+"v = h / (m * lambda)\n",
+"E = h^2 / (2 * m * lambda^2)\n",
+"E_ = h^2 / (2 * m_ * lambda^2)\n",
+"printf('\n Energy for electron is %f eV.\n Energy for neutron is %f eV.',E / e,E_ / e)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.38: Calculation_of_deBroglie_wavelength.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"E1 = 500 // kinetic energy of electron in first case in eV\n",
+"E2 = 50 // kinetic energy of electron in second case in eV\n",
+"E3 = 1 // kinetic energy of electron in third case in eV\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"e = 1.6e-19 // charge on an electron in C \n",
+"m = 9.1e-31 // mass of electron in kg\n",
+"// Sample Problem 38 on page no. 14.36\n",
+"printf('\n # PROBLEM 38 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' lambda = h/(2*m*E)^1/2.\n')\n",
+"lambda1 = h / sqrt(2 * m * E1 * e)\n",
+"lambda2 = h / sqrt(2 * m * E2 * e)\n",
+"lambda3 = h / sqrt(2 * m * E3 * e)\n",
+"printf('\n de-Broglie wavelength of electron - (1) In first case is %f A. \n (2) In second case is %f A. \n (3) In third is %f A.',lambda1*1e10,lambda2*1e10,lambda3*1e10)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.39: Calculation_of_Ratio_of_deBroglie_wavelengths.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"E1 = 1 // kinetic energy of neutron in first case in eV\n",
+"E2 = 510 // kinetic energy of neutron in second case in eV\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"e = 1.6e-19 // charge on an electron in C \n",
+"m = 1.67e-27 // mass of neutron in kg\n",
+"// Sample Problem 39 on page no. 14.36\n",
+"printf('\n # PROBLEM 39 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' lambda = h/(2*m*E)^1/2\n')\n",
+"lambda1 = h / sqrt(2 * m * E1 * e)\n",
+"lambda2 = h / sqrt(2 * m * E2 * e)\n",
+"r = lambda1 / lambda2\n",
+"printf('\n Ratio of de-Broglie wavelengths is %f .',r)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.3: Calculation_of_Energy_of_photon.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 4e-7 // wavelength of spectral line in meter\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"c = 3e8 // speed of light in m/sec\n",
+"e = 1.6e-19 // charge on an electron in C \n",
+"// Sample Problem 3 on page no. 14.20\n",
+"printf('\n # PROBLEM 3 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' E = h*c/lambda \n')\n",
+"E = (h * c) / lambda\n",
+"printf('\n Energy of photon is %e J.',E)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.40: Calculation_of_Ratio_of_deBroglie_wavelengths.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"E = 20 // kinetic energy of proton in MeV\n",
+"E2 = 510 // kinetic energy of neutron in second case in eV\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"e = 1.6e-19 // charge on an electron in C \n",
+"m = 1.67e-27 // mass of proton in kg\n",
+"m_ = 9.1e-31 // mass of electron in kg\n",
+"// Sample Problem 40 on page no. 14.37\n",
+"printf('\n # PROBLEM 40 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' lambda = h/(2*m*E)^1/2\n')\n",
+"lambda1 = h / sqrt(2 * m * 10^6 * E * e)\n",
+"lambda2 = h / sqrt(2 * m_ * E * 10^6 * e)\n",
+"r = lambda2 / lambda1\n",
+"printf('\n Ratio of de-Broglie wavelengths is %f.',r)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.41: Calculation_of_Velocity.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"E = 1 // kinetic energy of proton in MeV\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"e = 1.6e-19 // charge on an electron in C \n",
+"m = 1.67e-27 // mass of proton in kg\n",
+"// Sample Problem 41 on page no. 14.37\n",
+"printf('\n # PROBLEM 41 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' E = 1/2 * m*v^2 \n')\n",
+"v = sqrt(2 * E * 1.6e-13 / m)\n",
+"printf('\n Velocity is %e m/sec.\n From the above result it is clear that the velocity of proton is nearly one twentieth of the velocity of light. So the relativistic calculation are not required.',v)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.42: Calculation_of_deBroglie_wavelength.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"r = 1 / 20 // ratio of velocity of proton to the velocity of light \n",
+"c = 3e8 // velocity of light in m/sec\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"e = 1.6e-19 // charge on an electron in C \n",
+"m = 1.67e-27 // mass of proton in kg\n",
+"// Sample Problem 42 on page no. 14.38\n",
+"printf('\n # PROBLEM 42 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' lambda = h/(m*v)\n')\n",
+"v = r * c\n",
+"lambda = h / (m * v)\n",
+"printf('\n de-Broglie wavelength is %e m.',lambda)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.43: Calculation_of_kinetic_energy.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 5e-7 // wavelength in m\n",
+"c = 3e8 // velocity of light in m/sec\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"e = 1.6e-19 // charge on an electron in C \n",
+"m = 1.67e-27 // mass of proton in kg\n",
+"m_ = 9.1e-31 // mass of electron in kg\n",
+"// Sample Problem 43 on page no. 14.38\n",
+"printf('\n # PROBLEM 43 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' lambda = h/(2*m*E)^1/2\n')\n",
+"E1 = h^2 / (2 * m * lambda^2)\n",
+"E2 = h^2 / (2 * m_ * lambda^2)\n",
+"disp(E1,'kinetic energy of proton(in J) =')\n",
+"disp(E2,'kinetic energy of electron(in J) =')\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.44: Calculation_of_deBrogli_wavelength.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"n = 1 // no. of Bohr's orbit of hydrogen atom\n",
+"c = 3e8 // velocity of light in m/sec\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"e = 1.6e-19 // charge on an electron in C \n",
+"m = 9.1e-31 // mass of electron in kg\n",
+"// Sample Problem 44 on page no. 14.38\n",
+"printf('\n # PROBLEM 44 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' E = (13.6 / n^2)\n')\n",
+"E = (13.6 / n^2) * e\n",
+"lambda = h / sqrt(2 * m * E)\n",
+"printf('\n de-Broglie wavelength is %f Angstrom.',lambda*1e10)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.45: Calculation_of_Ratio_of_deBroglie_wavelengths.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"t = 300 // temperature in K\n",
+"k = 1.376e-23 // Boltzmann's constant in J/K\n",
+"c = 3e8 // velocity of light in m/sec\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"e = 1.6e-19 // charge on an electron in C \n",
+"m_ = 4 * 1.67e-27 // mass of helium atom in kg\n",
+"m = 1.67e-27 // mass of hydrogen atom in kg\n",
+"// Sample Problem 45 on page no. 14.39\n",
+"printf('\n # PROBLEM 45 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' lambda = h/(3*m*k*T)^1/2\n')\n",
+"lambda1 = h / sqrt(3 * m * k * t)\n",
+"lambda2 = h / sqrt(3 * m_ * k * t)\n",
+"r = lambda1 / lambda2\n",
+"printf('\n Ratio of de-Broglie wavelengths is %d .',r)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.47: Calculation_of_Group_velocity_and_Phase_velocity.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 1.2e-10 // DE Broglie wavelength in m\n",
+"c = 3e8 // velocity of light in m/sec\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"e = 1.6e-19 // charge on an electron in C \n",
+"m = 9.1e-31 // mass of electron in kg\n",
+"// Sample Problem 47 on page no. 14.40\n",
+"printf('\n # PROBLEM 47 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' lambda = h/(m*v)\n')\n",
+"v1 = h / (m * lambda)\n",
+"v2 = h / (2 * m * lambda)\n",
+"printf('\n Group velocity is %e m/sec.\n Phase velocity is %e m/sec.',v1,v2)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.4: Calculation_of_Number_of_photons_of_green_light.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 5e-7 // wavelength of green light in meter\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"c = 3e8 // speed of light in m/sec\n",
+"e = 1.6e-19 // charge on an electron in C \n",
+"P = 1 // energy in erg\n",
+"// Sample Problem 4 on page no. 14.21\n",
+"printf('\n # PROBLEM 4 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' E = h*c/lambda \n')\n",
+"E = ((h * c) / lambda) * (10^7)\n",
+"n = P / E\n",
+"printf('\n Number of photons of green light emitted is %e .',n)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.5: Calculation_of_Wavelength.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"E = 5e-19 // energy of photon in J\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"c = 3e8 // speed of light in m/sec\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"// Sample Problem 5 on page no. 14.21\n",
+"printf('\n # PROBLEM 5 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' E = h*c/lambda \n')\n",
+"lambda = c * h / E\n",
+"printf('\n Wavelength is %f Angstrom.',lambda * 10^10)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.6: Calculation_of_Energy_of_an_electron.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 4.35e-7 // wavelength of green light in meter\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"c = 3e8 // speed of light in m/sec\n",
+"e = 1.6e-19 // charge on an electron in C \n",
+"P = 1 // energy in erg\n",
+"// Sample Problem 6 on page no. 14.21\n",
+"printf('\n # PROBLEM 6 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' E = h*c/lambda \n')\n",
+"E = ((h * c) / lambda)\n",
+"printf('\n Energy of an electron is %e J.',E)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.7: Calculation_of_Energy_received_by_the_eye.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 5.6e-7 // wavelength of light in meter\n",
+"n = 120 // no. of photons per second\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"c = 3e8 // speed of light in m/sec\n",
+"e = 1.6e-19 // charge on an electron in C \n",
+"// Sample Problem 7 on page no. 14.22\n",
+"printf('\n # PROBLEM 7 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' E = h*c/lambda \n')\n",
+"E = ((h * c) / lambda)\n",
+"p = E * n\n",
+"printf('\n Energy received by the eye per second is %e W.',p)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.8: Calculation_of_Number_of_photons_of_yellow_light.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 5.5e-7 // wavelength of light in meter\n",
+"E = 1.5 // energy in J\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"c = 3e8 // speed of light in m/sec\n",
+"e = 1.6e-19 // charge on an electron in C \n",
+"// Sample Problem 8 on page no. 14.22\n",
+"printf('\n # PROBLEM 8 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' E = h*c/lambda \n')\n",
+"E_ = ((h * c) / lambda)\n",
+"n = E / E_\n",
+"printf('\n Number of photons of yellow light = %e .',n)\n",
+"                                                               "
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 14.9: Calculation_of_Work_function_and_Stopping_potential_and_Maximum_velocity.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 4.35e-7 // wavelength of light in meter\n",
+"lambda_ = 5.42e-7 // threshold wavelength of photoelectron in meter\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"c = 3e8 // speed of light in m/sec\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"m = 9.1e-31 // mass of an electron in kg \n",
+"// Sample Problem 9 on page no. 14.22\n",
+"printf('\n # PROBLEM 9 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' 1/2 m*v^2 = eV \n  E = h*c/lambda \n')\n",
+"w = ((h * c) / lambda_)\n",
+"v = sqrt(((2 * h * c) / m) * (1 / lambda - 1 / lambda_))\n",
+"V = m * v^2 / (2 * e)\n",
+"printf('\n Work function is %e J.\n Stopping potential is %f V.\n Maximum velocity is %e m/sec.',w,V,v)\n",
+"                                                               "
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Engineering_Physics_by_H_K_Malik/15-QUANTUM_MECHANICS.ipynb b/Engineering_Physics_by_H_K_Malik/15-QUANTUM_MECHANICS.ipynb
new file mode 100644
index 0000000..bb225ef
--- /dev/null
+++ b/Engineering_Physics_by_H_K_Malik/15-QUANTUM_MECHANICS.ipynb
@@ -0,0 +1,767 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 15: QUANTUM MECHANICS"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 15.10: Calculation_of_Uncertainty_in_determining_the_position.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"v = 3e7 // speed of electron in m/sec \n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"m = 9.1e-31 // mass of electron in kg\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"c = 3e8 // speed of light in m/sec\n",
+"// Sample Problem 10 on page no. 15.28\n",
+"printf('\n # PROBLEM 10 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' del_x*del_p = h/(4*pi) \n m = m_0/(1-(v^2/c^2))^1/2 \n')\n",
+"delta_p = m * v / sqrt(1 - (v/c)^2)\n",
+"delta_x = h / (4 * %pi * delta_p)\n",
+"printf('\n Uncertainty in determining the position is %e m.',delta_x)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 15.11: Calculation_of_Minimum_error_in_measurement_of_the_energy.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"t = 2.5e-14 // life time of hydrogen atom in exited state in sec\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"// Sample Problem 11 on page no. 15.28\n",
+"printf('\n # PROBLEM 11 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' del_E*del_t = h/(4*pi) \n')\n",
+"delta_E = h / (4 * %pi * t)\n",
+"printf('\n Minimum error in measurement of the energy is %e J.',delta_E)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 15.12: Calculation_of_Minimum_uncertainty_in_frequency.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"t = 10^-8 // life time of atom in exited state in sec\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"// Sample Problem 12 on page no. 15.28\n",
+"printf('\n # PROBLEM 12 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' del_E*del_t = h/(4*pi) \n')\n",
+"delta_f = 1 / (4 * %pi * t)\n",
+"printf('\n Minimum uncertainty in frequency is %e Hz.',delta_f)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 15.13: Calculation_of_Ratio_of_uncertainty_in_velocity_of_a_proton_and_an_electron.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"delta_x = 20e-10 // uncertainty in position in m\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"m = 9.1e-31 // mass of electron in kg\n",
+"m_ = 1.67e-27 // mass of proton in kg\n",
+"c = 3e8 // speed of light in m/sec\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"// Sample Problem 13 on page no. 15.29\n",
+"printf('\n # PROBLEM 13 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' del_x*del_p = h/(4*pi) \n')\n",
+"delta_v1 = h / (4 * %pi * m * delta_x)\n",
+"delta_v2 = h / (4 * %pi * m_ * delta_x)\n",
+"r = delta_v2 / delta_v1\n",
+"printf('\n Ratio of uncertainty in velocity of a proton and an electron is %e. ',r)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 15.14: Calculation_of_Energy_of_electron.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"delta_x = 1e-10 // width of box in m\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"m = 9.1e-31 // mass of electron in kg\n",
+"c = 3e8 // speed of light in m/sec\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"// Sample Problem 14 on page no. 15.29\n",
+"printf('\n # PROBLEM 14 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' E = (n^2 * h^2) / (8 * m * L^2)) \n')\n",
+"n = 1 // for n=1\n",
+"E = (n^2 * h^2) / (8 * m * delta_x^2)\n",
+"n = 2 // for n=2\n",
+"E_ = (n^2 * h^2) / (8 * m * delta_x^2)\n",
+"printf('\n Energy of electron - \n For (n=1) energy is %e J.\n For (n=2) energy is %e J.',E,E_)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 15.15: Calculation_of_Energy_difference.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"l = 1e-10 // width of box in m\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"m = 9.1e-31 // mass of electron in kg\n",
+"c = 3e8 // speed of light in m/sec\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"// Sample Problem 15 on page no. 15.30\n",
+"printf('\n # PROBLEM 15 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' E = (n^2 * h^2) / (8 * m * L^2)) \n')\n",
+"n = 1 // for n=1\n",
+"E = (n^2 * h^2) / (8 * m * l^2)\n",
+"n = 2 // for n=2\n",
+"E_ = (n^2 * h^2) / (8 * m * l^2)\n",
+"d = E_ - E\n",
+"printf('\n Energy difference is %e J.',d)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 15.16: Calculation_of_Energy_difference.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"l = 3e-10 // width of box in m\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"m = 9.1e-31 // mass of electron in kg\n",
+"c = 3e8 // speed of light in m/sec\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"// Sample Problem 16 on page no. 15.30\n",
+"printf('\n # PROBLEM 16 # \n')\n",
+"printf('Standard Formula used \n')\n",
+"printf(' E = (n^2 * h^2) / (8 * m * L^2)) \n')\n",
+"n = 1 // For n=1\n",
+"E = (n^2 * h^2) / (8 * m * l^2)\n",
+"n = 2 // For n=2\n",
+"E_ = (n^2 * h^2) / (8 * m * l^2)\n",
+"n = 3 // For n=3\n",
+"E__ = (n^2 * h^2) / (8 * m * l^2)\n",
+"printf('\n Energy of electron -\n For (n=1) is %e J.\n For (n=2) is %e J.\n For (n=3) is %e J.',E,E_,E__)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 15.17: Calculation_of_Energy_difference.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"l = 2.5e-10 // width of box in m\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"m = 9.1e-31 // mass of electron in kg\n",
+"c = 3e8 // speed of light in m/sec\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"// Sample Problem 17 on page no. 15.30\n",
+"printf('\n # PROBLEM 17 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' E = (n^2 * h^2) / (8 * m * L^2)) \n')\n",
+"n = 1 // for n=1\n",
+"E = (n^2 * h^2) / (8 * m * l^2)\n",
+"n = 2 // for n=2\n",
+"E_ = (n^2 * h^2) / (8 * m * l^2)\n",
+"printf('\n Energy of electron -\n For (n=1) is %e J.\n For (n=2) is %e J.',E,E_)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 15.18: Calculation_of_Lowest_energy_of_neutron_confined_in_the_nucleus.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"l = 1e-14 // width of box in m\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"m = 1.67e-27 // mass of neutron in kg\n",
+"c = 3e8 // speed of light in m/sec\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"// Sample Problem 18 on page no. 15.31\n",
+"printf('\n # PROBLEM 18 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' E = (n^2 * h^2) / (8 * m * L^2)) \n')\n",
+"n = 1 // for n=1\n",
+"E = (n^2 * h^2) / (8 * m * l^2)\n",
+"printf('\n Lowest energy of neutron confined in the nucleus is %e J.',E)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 15.19: Calculation_of_Energy_of_electron_and_Momentum_of_electron.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"l = 1e-10 // width of box in m\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"m = 9.1e-31 // mass of electron in kg\n",
+"c = 3e8 // speed of light in m/sec\n",
+"h = 6.63e-34 // Planck constant in J-sec\n",
+"// Sample Problem 19 on page no. 15.31\n",
+"printf('\n # PROBLEM 19 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' E = (n^2 * h^2) / (8 * m * L^2)) \n p_n = n*h/(2*pi) \n')\n",
+"n = 1 // for n=1\n",
+"p1 = (n * h) / (2 * l)\n",
+"E = (n^2 * h^2) / (8 * m * l^2)\n",
+"n = 2 // for n=2\n",
+"p2 = (n * h) / (2 * l)\n",
+"E_ = (n^2 * h^2) / (8 * m * l^2)\n",
+"printf('\n Energy of electron -\n For (n=1) is %e J.\n For (n=2) is %e J.\n Momentum of electron -\n For (n=1) is %e kg-m/sec.\n For (n=2) is %e kg-m/sec.',E,E_,p1,p2)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 15.1: Calculation_of_Percentage_of_uncertainty_in_momentum.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that \n",
+"E = 1000 // energy of electron in eV\n",
+"delta_x = 1e-10 // error in position in m\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"m = 9.1e-31 // mass of electron in kg\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"// Sample Problem 1 on page no. 15.24\n",
+"printf('\n # PROBLEM 1 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' p = (2 * m * E * e)^(1/2) \n')\n",
+"p = sqrt(2 * m * E * e)\n",
+"delta_p = h / (4 * %pi * delta_x)\n",
+"P = (delta_p / p) * 100\n",
+"printf('\n Percentage of uncertainty in momentum is %f.',P)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 15.20: Calculation_of_Energy_Eigen_value_of_electron_and_deBroglie_wavelength.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"l = 1e-10 // length of box in m\n",
+"m = 9.1e-31 // mass of electron in kg\n",
+"c = 3e8 // speed of light in m/sec\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"// Sample Problem 20 on page no. 15.32\n",
+"printf('\n # PROBLEM 20 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' E = (n^2 * h^2) / (8 * m * L^2)) \n p_n = n*h/(2*pi) \n')\n",
+"n = 1 // for n=1\n",
+"E1 = (n^2 * h^2) / (8 * m * l^2)\n",
+"lambda1 =2*l\n",
+"n = 2 // for n=2\n",
+"E2 = (n^2 * h^2) / (8 * m * l^2)\n",
+"lambda2 =2*l/2\n",
+"n = 3 // for n=3\n",
+"E3 = (n^2 * h^2) / (8 * m * l^2)\n",
+"lambda3 =2*l/3\n",
+"printf('\n Energy Eigen value of electron -\n For (n=1) is %e J.\n For (n=2) is %e J.\n For (n=3) is %e J. \nde-Broglie wavelength of electron -\n For (n=1) is %f A.\n For (n=2) is %f A. \n For (n=3) is %f A',E1,E2,E3,lambda1*1e10,lambda2*1e10,lambda3*1e10)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 15.21: Calculation_of_Energy_Eigen_values.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"E1 = 3.2e-18 // minimum energy possible for a particle entrapped in a one dimensional box in J\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"m = 9.1e-31 // mass of electron in kg\n",
+"c = 3e8 // speed of light in m/sec\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"// Sample Problem 21 on page no. 15.32\n",
+"printf('\n # PROBLEM 21 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' E = (n^2 * h^2) / (8 * m * L^2)) \n')\n",
+"E1 = E1 / e // in eV\n",
+"n = 2 // for n=2\n",
+"E2 = n^2 * E1\n",
+"n = 3 // for n=3\n",
+"E3 = n^2 * E1\n",
+"n = 4 // for n=4\n",
+"E4 = n^2 * E1\n",
+"printf('\n Energy Eigen values -\n For (n=2) for %f eV.\n For (n=3) is %f eV.\n For (n=4) is %f eV.',E2,E3,E4)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 15.22: Calculation_of_Order_of_exited_state.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"l = 4e-10 // width of box in m\n",
+"E = 9.664e-17 // energy of electron in J\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"m = 9.1e-31 // mass of electron in kg\n",
+"c = 3e8 // speed of light in m/sec\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"// Sample Problem 22 on page no. 15.33\n",
+"printf('\n # PROBLEM 22 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' E = (n^2 * h^2) / (8 * m * L^2)) \n p_n = n*h/(2*pi) \n')\n",
+"n = 1 // for n=1\n",
+"E1 = (n^2 * h^2) / (8 * m * l^2)\n",
+"N = sqrt(E / E1)\n",
+"p = ((N) * h) / (2 * l)\n",
+"printf('\n Order of exited state is %d.\n Momentum of electron is %e kg-m/sec.',N,p)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 15.23: Calculation_of_Energy_levels_of_electron_and_Energy_levels_of_marble.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"l = 10e-10 // width of box containing electron in m\n",
+"E = 9.664e-17 // energy of electron in J\n",
+"M = 0.001 // mass of glass marble in kg\n",
+"l_ = 0.2 // width of box containing marble in m\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"m = 9.1e-31 // mass of electron in kg\n",
+"c = 3e8 // speed of light in m/sec\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"// Sample Problem 23 on page no. 15.33\n",
+"printf('\n # PROBLEM 23 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' E = (n^2 * h^2) / (8 * m * L^2)) \n p_n = n*h/(2*pi) \n')\n",
+"// For electron\n",
+"n = 1 // for n=1\n",
+"E1 = (n^2 * h^2) / (8 * m * l^2)\n",
+"E2 = 2^2* E1\n",
+"E3 = 3^2 * E1\n",
+"// For glass marble\n",
+"E1_ = h^2/(8*M*l_^2)\n",
+"E2_ = 2^2 * E1_\n",
+"E3_ = 3^2 *E1_\n",
+"printf('\n Energy levels of electron \n For (n=1) is %e J.\n For (n=2) is %e J.\n For (n=3) is %e J.\n Energy levels of marble \n For (n=1) is %e J.\n For (n=2) is %e J.\n For (n=3) is %e J.',E1,E2,E3,E1_,E2_,E3_)\n",
+"printf('\n It is clear that the levels in case of marble are very small and are nearly zero. So it is not possible to measure them experimentally.')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 15.3: Calculation_of_Percentage_of_uncertainty_in_momentum.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that \n",
+"E = 500 // energy of electron in eV\n",
+"delta_x = 2e-10 // error in position in m\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"m = 9.1e-31 // mass of electron in kg\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"// Sample Problem 3 on page no. 15.25\n",
+"printf('\n # PROBLEM 3 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' p = (2 * m * E * e)^(1/2) \n')\n",
+"p = sqrt(2 * m * E * e)\n",
+"delta_p = h / (4 * %pi * delta_x)\n",
+"P = (delta_p / p) * 100\n",
+"printf('\n Percentage of uncertainty in momentum is %f.',P)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 15.4: Calculation_of_Uncertainty_in_position.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that \n",
+"delta_lambda = 1e-6 // accuracy in wavelength of its one part\n",
+"lambda = 1e-10 // wavelength of x-ray in m\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"// Sample Problem 4 on page no. 15.25\n",
+"printf('\n # PROBLEM 4 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' del_x*del_p = h/(4*pi) \n')\n",
+"delta_x = lambda / (4 * %pi * delta_lambda)\n",
+"printf('\n Uncertainty in position is %f micrometer.',delta_x*10^6)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 15.5: Calculation_of_Uncertainty_in_momentum.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that \n",
+"delta_x = 1e-10 // error in position in m\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"m = 9.1e-31 // mass of electron in kg\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"// Sample Problem 5 on page no. 15.26\n",
+"printf('\n # PROBLEM 5 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' del_x*del_p = h/(4*pi) \n')\n",
+"delta_p = h / (4 * %pi * delta_x)\n",
+"printf('\n Uncertainty in momentum is %e kg m/sec.',delta_p)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 15.6: Calculation_of_Uncertainty_in_position.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that \n",
+"M = 5.4e-26 // momentum of electron in kg-m/sec\n",
+"p = 0.05 // percentage accuracy in momentum\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"m = 9.1e-31 // mass of electron in kg\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"// Sample Problem 6 on page no. 15.26\n",
+"printf('\n # PROBLEM 6 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' del_x*del_p = h/(4*pi) \n')\n",
+"delta_m = p * M / 100\n",
+"delta_x = h / (4 * %pi * delta_m)\n",
+"printf('\n Uncertainty in position is %f micrometre.',delta_x * 10^6)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 15.7: Calculation_of_Minimum_energy_of_electron.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that \n",
+"r = 0.53e-10 // radius of hydrogen atom in m\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"m = 9.1e-31 // mass of electron in kg\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"// Sample Problem 7 on page no. 15.27\n",
+"printf('\n # PROBLEM 7 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' del_x*del_p = h/(4*pi) \n p = (2 * m * E * e)^(1/2) \n')\n",
+"delta_M = h / (4 * %pi * r)\n",
+"delta_k = delta_M^2 / (2 * m)\n",
+"printf('\n Minimum energy of electron is %e J.',delta_k)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 15.8: Calculation_of_Uncertainty_in_determining_the_position_of_electron.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"v = 5e3 // speed of electron in m/sec\n",
+"a = 0.003 // percentage accuracy in measurement of speed \n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"m = 9.1e-31 // mass of electron in kg\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"// Sample Problem 8 on page no. 15.27\n",
+"printf('\n # PROBLEM 8 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' del_x*del_p = h/(4*pi) \n')\n",
+"delta_v = v * a / 100\n",
+"delta_p = m * delta_v\n",
+"delta_x = h / (4 * %pi * delta_p)\n",
+"printf('\n Uncertainty in determining the position of electron is %e m.',delta_x)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 15.9: Calculation_of_Uncertainty_in_determining_the_position.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"v = 6.6e4 // speed of electron in m/sec\n",
+"a = 0.01 // percentage accuracy in measurement of speed \n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"m = 9.1e-31 // mass of electron in kg\n",
+"h = 6.6e-34 // Planck constant in J-sec\n",
+"// Sample Problem 9 on page no. 15.27\n",
+"printf('\n # PROBLEM 9 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' del_x*del_p = h/(4*pi) \n')\n",
+"delta_v = v * a / 100\n",
+"delta_p = m * delta_v\n",
+"delta_x = h / (4 * %pi * delta_p)\n",
+"printf('\n Uncertainty in determining the position is %e m.',delta_x)"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Engineering_Physics_by_H_K_Malik/16-FREE_ELECTRON_THEORY.ipynb b/Engineering_Physics_by_H_K_Malik/16-FREE_ELECTRON_THEORY.ipynb
new file mode 100644
index 0000000..6a3b1ea
--- /dev/null
+++ b/Engineering_Physics_by_H_K_Malik/16-FREE_ELECTRON_THEORY.ipynb
@@ -0,0 +1,377 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 16: FREE ELECTRON THEORY"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 16.10: Calculation_of_Energy_difference.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"l = 1e-10 //length of box in m\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"m = 9.1e-31 // mass of electron in kg\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"// Sample Problem 10 on page no. 16.18\n",
+"printf('\n # PROBLEM 10 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf('E = (n^2 * h^2) / (8 * m * l^2) \n')\n",
+"n = 1 // for n=1\n",
+"E = (n^2 * h^2) / (8 * m * l^2)\n",
+"n = 2 // for n=2\n",
+"E_ = (n^2 * h^2) / (8 * m * l^2)\n",
+"d = (E_ - E) * (1 / e)\n",
+"printf('\n Energy difference is %f eV.',d)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 16.1: Calculation_of_Average_energy_of_electron_and_Speed_of_electron.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that \n",
+"t = 0 // temperature in K\n",
+"E = 10 // Fermi energy of electron in eV\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"m = 9.1e-31 // mass of electron in kg\n",
+"// Sample Problem 1 on page no. 16.14\n",
+"printf('\n # PROBLEM 1 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf('1/2 * m*v^2 = E_0 \n')\n",
+"E_ = E * 3 / 5\n",
+"v = sqrt(2 * E_ * e / m)\n",
+"printf('\n Average energy of electron is %f eV.\n Speed of electron is %e m/sec.',E_,v)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 16.2: Calculation_of_Average_energy_of_electron_and_Speed_of_electron.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that \n",
+"t = 0 // temperature in K\n",
+"E = 7.9 // Fermi energy in eV\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"m = 9.1e-31 // mass of electron in kg\n",
+"// Sample Problem 2 on page no. 16.14\n",
+"printf('\n # PROBLEM 2 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf('1/2 * m*v^2 = E_0 \n')\n",
+"E_ = E * 3 / 5\n",
+"v = sqrt(2 * E_ * e / m)\n",
+"printf('\n Average energy of electron is %f eV.\n Speed of electron is %e m/sec.',E_,v)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 16.3: Calculation_of_Fermi_energy_and_Speed_of_electron.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that \n",
+"n = 2.5e28 // no. of free electron in per meter cube\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"m = 9.1e-31 // mass of electron in kg\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"// Sample Problem 3 on page no. 16.15\n",
+"printf('\n # PROBLEM 3 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf('1/2 * m*v^2 = E_0 \n ')\n",
+"printf('E_0 = (h^2 /(8 * pi^2 * m))*(3 * pi^2 * n)^(2/3) * (1 / e)\n')\n",
+"E = (h^2 / (8 * %pi^2 * m)) * (3 * %pi^2 * n)^(2/3) * (1 / e)\n",
+"v = (h / (2 * %pi * m)) * (3 * %pi^2 * n)^(1/3)\n",
+"printf('\n Fermi energy is %f eV.\n Speed of electron is %e m/sec.',E,v)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 16.4: Calculation_of_Fermi_energy_and_Average_energy.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that \n",
+"d = 8940 // density of copper in kg/m^3\n",
+"w = 63.55 // atomic weight of copper\n",
+"t = 0 // temperature in K\n",
+"N = 6.02e26 // Avogadro no. in per kg\n",
+"m = 9.1e-31 // mass of electron in kg\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"// Sample Problem 4 on page no. 16.15\n",
+"printf('\n # PROBLEM 4 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf('1/2 * m*v^2 = E_0 \n ')\n",
+"printf('E = (h^2 / (8 * pi^2 * m)) * (3 * pi^2 * N/V)^(2/3) \n')\n",
+"V = w / d\n",
+"n = N / V \n",
+"E = (h^2 / (8 * %pi^2 * m)) * (3 * %pi^2 * n)^(2/3) * (1 / e)\n",
+"E_ = 3 * E / 5\n",
+"printf('\n Fermi energy is %f eV.\n Average energy is %f eV.',E,E_)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 16.5: Calculation_of_Fermi_energy.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that \n",
+"d = 10.5e6 // density of silver in g/m^3\n",
+"w = 108 // atomic weight of silver\n",
+"t = 0 // temperature in K\n",
+"N = 6.02e23 // Avogadro no. in per kg\n",
+"m = 9.1e-31 // mass of electron in kg\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"// Sample Problem 5 on page no. 16.16\n",
+"printf('\n # PROBLEM 5 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf('E = (h^2 / (8 * pi^2 * m)) * (3 * pi^2 * N/V)^(2/3) \n')\n",
+"V = w / d\n",
+"n = N / V \n",
+"E = (h^2 / (8 * %pi^2 * m)) * (3 * %pi^2 * n)^(2/3) * (1 / e)\n",
+"printf('\n Fermi energy is %f eV.',E)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 16.6: Calculation_of_Fermi_energy_and_Fermi_vector_and_Total_kinetic_energy.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that \n",
+"a = 4e-10 // lattice constant in mr\n",
+"t = 0 // temperature in K\n",
+"N = 6.02e23 // Avogadro no. in per kg\n",
+"m = 9.1e-31 // mass of electron in kg\n",
+"h = 6.62e-34 // Planck constant in J-sec\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"// Sample Problem 6 on page no. 16.16\n",
+"printf('\n # PROBLEM 6 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf('E = (h^2 / (8 * pi^2 * m)) * (3 * pi^2 * N/V)^(2/3) \n')\n",
+"V = a^3\n",
+"n = 4 / V \n",
+"E = (h^2 / (8 * %pi^2 * m)) * (3 * %pi^2 * n)^(2/3) * (1 / e)\n",
+"k = (3 * %pi^2 *n)^(1/3)\n",
+"KE = (3 * E / 5) * (n)\n",
+"printf('\n Fermi energy is %f eV.\n Fermi vector is %e per m.\n Total kinetic energy is %e eV.',E,k,KE)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 16.7: Calculation_of_Drift_velocity_of_electron.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"d = 0.9e-3 // diameter of aluminium in m\n",
+"i = 6 // current in amp\n",
+"n = 4.5e28 // no. of electron available for conduction per meter^3 \n",
+"e =  1.6e-19 // charge on an electron in C\n",
+"// Sample Problem 7 on page no. 16.17\n",
+"printf('\n # PROBLEM 7 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf('J = I*A \n v_d = J/ne \n')\n",
+"J = i * 4 / (%pi * (d)^2)\n",
+"v = J / (n * e)\n",
+"printf('\n Drift velocity of electron is %e m/sec.',v)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 16.8: Calculation_of_Current_density_and_Drift_velocity.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that \n",
+"d = 8.92e3 // density of copper in kg/m^3\n",
+"i = 5 // current in amp\n",
+"w = 63.5 // atomic weight of copper\n",
+"r = 0.7e-3 // radius in meter\n",
+"N = 6.02e28 // Avogadro no.\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"// Sample Problem 8 on page no. 16.17\n",
+"printf('\n # PROBLEM 8 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' J = I*A \n v_d = J/ne \n')\n",
+"V = (w / d)\n",
+"n = N / V \n",
+"J = i / (%pi * r^2)\n",
+"v = J / (n * e)\n",
+"printf('\n Current density = %e amp/m^2.\n Drift velocity is %e m/sec.',J,v)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 16.9: Calculation_of_Fermi_Energy.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"d1= 0.534*10^3 // densiy of Li in kg/m^3\n",
+"d2= 0.971*10^3 // densiy of Na in kg/m^3\n",
+"d3= 0.86*10^3 // densiy of K in kg/m^3\n",
+"w1 = 6.939 // atomic weight of Li \n",
+"w2 = 22.99 // atomic weight of Na\n",
+"w3 = 39.202 // atomic weight of K\n",
+"h = 6.62e-34 // Planck constant in J sec\n",
+"m = 9.1e-31 // mass of an electron in kg\n",
+"NA = 6.023e26 // Avogadro no.\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"// Sample Problem 9 on page no. 16.17\n",
+"printf('\n # PROBLEM 9 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf('E = h^2 / (8 * m * pi^2) * (3*pi^2*N/V)^2/3 \n')\n",
+"// For Li\n",
+"n1 = NA * d1/w1\n",
+"E1 = h^2/(8*%pi^2*m)*(3*%pi^2*n1)^(2/3)\n",
+"// For Na\n",
+"n2 = NA * d2/w2\n",
+"E2 = h^2/(8*%pi^2*m)*(3*%pi^2*n2)^(2/3)\n",
+"// For K\n",
+"n3 = NA * d3/w3\n",
+"E3 = h^2/(8*%pi^2*m)*(3*%pi^2*n3)^(2/3)\n",
+"printf('\n Fermi Energy \n For Li is %f eV.\n For Na is %f eV. \n For K is %f eV',E1/e,E2/e,E3/e)"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Engineering_Physics_by_H_K_Malik/17-BAND_THEORY_OF_SOLIDS.ipynb b/Engineering_Physics_by_H_K_Malik/17-BAND_THEORY_OF_SOLIDS.ipynb
new file mode 100644
index 0000000..51a4fa1
--- /dev/null
+++ b/Engineering_Physics_by_H_K_Malik/17-BAND_THEORY_OF_SOLIDS.ipynb
@@ -0,0 +1,216 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 17: BAND THEORY OF SOLIDS"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 17.1: EX17_1.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that \n",
+"a = 3e-10 // side of square lattice in m\n",
+"h = 6.62e-34 // Planck constant in J sec\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"m = 9.1e-31 // mass of electron in kg\n",
+"// Sample Problem 1 on page no. 17.18\n",
+"printf('\n # PROBLEM 1 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf('E = P^2 / (2*m) \n P = h_cut*k \n')\n",
+"p = (h / (2 * a))\n",
+"E = (p^2 / (2 * m)) * (1 / e)\n",
+"printf('\n Electron momentum value at the sides of first Brilloin zone is %e kg-m/sec.\n Enrgy of free electron is %f eV.',p,E)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 17.2: Calculation_of_Position_of_Fermi_level.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that \n",
+"n = 5e22 // no. of atoms per m^3\n",
+"t = 300 // room temperature in K\n",
+"k = 1.37e-23 // Boltzmann's constant in J/K\n",
+"h = 6.62e-34 // Planck constant in J sec\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"m = 9.1e-31 // mass of electron in kg\n",
+"// Sample Problem 2 on page no. 17.19\n",
+"printf('\n # PROBLEM 2 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf('n_c = 2*(2*pi*m*k*T/h^2)^(3/2) * e^(E_f-E_c)/kT \n')\n",
+"d = (k * t) * log(n * h^3 / (2 * (2 * %pi * m * k * t)^(3/2)))\n",
+"printf('\n Position of fermi level is %f eV.',-d/e)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 17.3: Calculation_of_New_position_of_Fermi_level.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that \n",
+"E = 0.3 // Fermi energy in eV\n",
+"T = 330 // temperature in K\n",
+"t = 300 // room temperature in K\n",
+"k = 1.37e-23 // Boltzmann's constant in J/K\n",
+"h = 6.62e-34 // Planck constant in J sec\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"m = 9.1e-31 // mass of electron in kg\n",
+"// Sample Problem 3 on page no. 17.19\n",
+"printf('\n # PROBLEM 3 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf('n_c = n_d * e^(E_f-E_c)/kT \n')\n",
+"d = (T / t) * (E)\n",
+"printf('\n New position of fermi level is %f eV.',d)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 17.4: Calculation_of_Density_of_holes_and_electron.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that \n",
+"E = 0.7 // band gap for semiconductor in eV\n",
+"t = 300 // room temperature in K\n",
+"k = 1.38e-23 // Boltzmann's constant in J/K\n",
+"h = 6.62e-34 // Planck constant in J sec\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"m = 9.1e-31 // mass of electron in kg\n",
+"// Sample Problem 4 on page no. 17.20\n",
+"printf('\n # PROBLEM 4 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf('n_c = 2*(2*pi*m*k*T/h^2)^(3/2) * e^(E_f-E_c)/kT \n')\n",
+"n = 2 * ((2 * %pi * k * t * m) / h^2)^(3/2) * exp(-(E * e / (2 * k * t)))\n",
+"printf('\n Density of holes and electron is %e per m^3.',n)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 17.5: Calculation_of_Hall_coefficient.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that \n",
+"n = 5e28 // no. of atoms in per m^3\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"// Sample Problem 5 on page no. 17.20\n",
+"printf('\n # PROBLEM 5 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf('R_h = 1/(n*e) \n')\n",
+"R = -(1 / (n * e))\n",
+"printf('\n Hall coefficient is %e m^3/C.',R)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 17.6: Calculation_of_Hall_coefficient.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that \n",
+"a = 4.28e-10 // cell side of Na in m\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"// Sample Problem 6 on page no. 17.20\n",
+"printf('\n # PROBLEM 6 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf('R_h = 1/(n*e) \n')\n",
+"n = (2 / a^3)\n",
+"R = -(1 / (n * e))\n",
+"printf('\n Hall coefficient is %e m^3/C.',R)"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Engineering_Physics_by_H_K_Malik/18-MAGNETIC_PROPERTIES_OF_SOLIDS.ipynb b/Engineering_Physics_by_H_K_Malik/18-MAGNETIC_PROPERTIES_OF_SOLIDS.ipynb
new file mode 100644
index 0000000..aeb265b
--- /dev/null
+++ b/Engineering_Physics_by_H_K_Malik/18-MAGNETIC_PROPERTIES_OF_SOLIDS.ipynb
@@ -0,0 +1,691 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 18: MAGNETIC PROPERTIES OF SOLIDS"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 18.10: Calculation_of_Number_of_ampere_turns.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that \n",
+"l = 1 // length of iron rod in m\n",
+"a = 4e-4 // area in m^2\n",
+"mu = 50e-4 // permeability of iron in H/m\n",
+"Phi = 4e-4 // magnetic flux in Weber\n",
+"// Sample Problem 10 on page no. 18.24\n",
+"printf('\n # PROBLEM 10 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf('B = mu*N*I \n')\n",
+"B = Phi / a\n",
+"NI = B / mu\n",
+"printf('\n Number of ampere turns is %d A/m. ',NI)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 18.11: Calculation_of_Current_through_the_winding.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that \n",
+"n = 200 // no. of turns \n",
+"l = 0.5 // the mean length of iron wire in m\n",
+"phi = 4e-4 // magnetic flux in Weber\n",
+"a = 4e-4 // area of cross section in m^2\n",
+"mu = 6.5e-4 // permeability of iron in wb/Am\n",
+"mu_ = 4 * %pi * 1e-7 // magnetic permeability of space\n",
+"// Sample Problem 11 on page no. 18.25\n",
+"printf('\n # PROBLEM 11 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf('B = mu*N*I \n')\n",
+"B = phi / a\n",
+"N = n / l\n",
+"I = B / (mu * N)\n",
+"printf('\n Current through the winding is %f A. ',I)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 18.12: Calculation_of_Radius_of_atom.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that \n",
+"X = -5.6e-6 // magnetic susceptibility of material\n",
+"a = 2.55e-10 // lattice constant in m\n",
+"H = 1e4 // magnetic field in A/m\n",
+"mu_ = 4 * %pi * 1e-7 // magnetic permittivity of space\n",
+"m = 9.1e-31 // mass of electron in kg\n",
+"e = 1.6e-19 // charge in an electron in C\n",
+"// Sample Problem 12 on page no. 18.25\n",
+"printf('\n # PROBLEM 12 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf('  Chi = mu_0*Z*e^2 *N*R^2 /(6*m) \n')\n",
+"N = 2 / a^3\n",
+"z = 1 \n",
+"R = ((-X * 6 * m) / (mu_ * z * e^2 * N))^(1/2)\n",
+"printf('\n Radius of  atom is %f A.',R * 1e10)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 18.13: Calculation_of_Susceptibility.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that \n",
+"N = 6.5e25 // no. of atom per m^3\n",
+"T = 300 // room temperature in K\n",
+"mu_ = 4 * %pi * 1e-7 // magnetic permittivity of space\n",
+"k = 1.38e-23 // Boltzmann's constant in J/K\n",
+"m = 9.1e-31 // mass of electron in kg\n",
+"e = 1.6e-19 // charge in an electron in C\n",
+"h = 6.62e-34 // Planck constant in J sec\n",
+"// Sample Problem 13 on page no. 18.25\n",
+"printf('\n # PROBLEM 13 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf('  Chi = mu_0*N*M^2 /(3*k*t) \n')\n",
+"M = (e * h) / (4 * %pi * m)\n",
+"X = (mu_ * N * M^2) / (3 * k * T)\n",
+"printf('\n Susceptibility is %e',X)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 18.14: Calculation_of_Magnetization.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that \n",
+"w = 168.5 // molecular weight \n",
+"d = 4370 // density of material in kg/m^3\n",
+"H = 2e5 // magnetic field in A/m\n",
+"T = 300 // room temperature in K\n",
+"mu_ = 4 * %pi * 1e-7 // magnetic permittivity of space]\n",
+"NA = 6.02e26 // Avogadro no. in per kg\n",
+"mu_b = 9.24e-24 // Bohr magnetons in Am^2\n",
+"k = 1.38e-23 // Boltzmann's constant in J/K\n",
+"// Sample Problem 14 on page no. 18.26\n",
+"printf('\n # PROBLEM 14 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf('  Chi = mu_0*N*M^2 /(3*k*t) \n')\n",
+"N = d * NA / w\n",
+"X = (mu_ * N * (2 * mu_b)^2) / (3 * k * T)\n",
+"I = X * H\n",
+"printf('\n Magnetisation is %f A/m',I)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 18.15: Calculation_of_Total_loss_of_energy.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"A = 2500 // area of hysteresis loop \n",
+"m = 10000 // weight in kg\n",
+"d = 7.5 // density of material in g/cm^3\n",
+"f = 50 // frequency in Hz\n",
+"// Sample Problem 15 on page no. 18.26\n",
+"printf('\n # PROBLEM 15 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf('  M = V*d \n')\n",
+"E = f * A * 3600\n",
+"V = m / d\n",
+"L = E * V\n",
+"printf('\n Total loss of energy per hour is %e ergs.',L)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 18.16: Calculation_of_Current_in_solenoid.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"H = 5e3 // coercivity in A/m\n",
+"l = 0.10 // length of solenoid in m\n",
+"n = 50 // no. of turns \n",
+"// Sample Problem 16 on page no. 18.27\n",
+"printf('\n # PROBLEM 16 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' H=N*i \n')\n",
+"N = n / l\n",
+"i = H / N\n",
+"printf('\n Current in solenoid should be %d A.',i)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 18.17: Calculation_of_Number_of_turns.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"l = 0.50 // length of iron rod in m\n",
+"a = 4e-4 // area of cross section of rod in m^2\n",
+"mu = 65e-4 // permeability of iron in H/m\n",
+"fi = 4e-5 // flux in weber \n",
+"// Sample Problem 17 on page no. 18.27\n",
+"printf('\n # PROBLEM 17 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf('  N =H*l \n')\n",
+"B = fi / a\n",
+"H = B / mu\n",
+"N = H * l\n",
+"printf('\n Number of turns are %f',N)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 18.18: Calculation_of_Permeability_and_Susceptibility.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"H = 600 // magnetic flux in A/m\n",
+"a = 0.2e-4 // area of cross section of rod in m^2\n",
+"phi = 2.4e-5 // flux in weber \n",
+"mu_ = 4*%pi * 1e-7 // permeability of space in N/A^2\n",
+"// Sample Problem 18 on page no. 18.27\n",
+"printf('\n # PROBLEM 18 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' mu_r = 1 + Chi \n')\n",
+"B = phi / a\n",
+"mu = B / H\n",
+"X = mu / mu_ - 1\n",
+"printf('\n Permeability is %f N/A^2.\n Susceptibility is %f.',mu,X)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 18.19: Calculation_of_Relative_permeability.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"X = 9.5e-9 // susceptibility of medium \n",
+"mu_ = 4*%pi * 1e-7 // permeability of space in N/A^2\n",
+"// Sample Problem 19 on page no. 18.28\n",
+"printf('\n # PROBLEM 19 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' mu_r = 1 + Chi \n')\n",
+"mu = mu_ * (1 + X)\n",
+"mu_r = mu / mu_\n",
+"printf('\n Relative permeability is 1 + %e',mu_r -1)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 18.1: Calculation_of_Magnetic_moment_and_Bohr_magneton.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that \n",
+"r = 0.53e-10 // radius of orbit in m\n",
+"f = 6.6e15 // frequency of revolution in Hz\n",
+"h = 6.6e-34 // Planck constant in J sec\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"m = 9.1e-31 // mass of electron in kg\n",
+"// Sample Problem 1 on page no. 18.21\n",
+"printf('\n # PROBLEM 1 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' M = I*a \n')\n",
+"M = e * f * %pi * r^2\n",
+"mu = (e * h) / (4 * %pi * m) \n",
+"printf('\n Magnetic moment is %e Am^2.\n Bohr magneton is %e J/T.',M,mu)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 18.20: Calculation_of_Energy_loss.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"a = 250 // area of the B-H loop in J/m^3\n",
+"f = 50 // frequency in Hz\n",
+"d = 7.5e3 // density of iron in kg/m^3\n",
+"m = 100 // mass of core in kg\n",
+"// Sample Problem 20 on page no. 18.28\n",
+"printf('\n # PROBLEM 20 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' M = V*d \n')\n",
+"V = m / d\n",
+"n = 3600 * f\n",
+"A = a * V * n\n",
+"printf('\n Energy loss per hour is %e J.',A)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 18.21: Calculation_of_Hysteresis_loss.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"B_max = 1.375 // maximum value of B in Wb/m^2\n",
+"a = 0.513 // area of the loop in cm^2\n",
+"k = 1000 // value of 1 cm on x axis in A/m\n",
+"k_ = 1 // value of 1 cm on y axis in Wb/m^2\n",
+"B = 1.375 // alternating magnetic flux density in Wb/m^2\n",
+"v = 1e-3 // volume of specimen in m^3\n",
+"f = 50 // frequency in Hz\n",
+"// Sample Problem 21 on page no. 18.28\n",
+"printf('\n # PROBLEM 21 # \n')\n",
+"printf('Standard formula used \n K = a * k * k_.\n')\n",
+"K = a * k * k_\n",
+"L = K * v * f\n",
+"printf('\n Hysteresis loss per sec is %f W',L)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 18.2: Calculation_of_Magnetization_and_Flux_density_and_Relative_permeability.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that \n",
+"X = -4.2e-6 // magnetic susceptibility\n",
+"H = 1.19e5 // magnetic field in A/m\n",
+"mu_ = 4 * %pi * 1e-7 // magnetic permeability of space\n",
+"// Sample Problem 2 on page no. 18.21\n",
+"printf('\n # PROBLEM 2 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' I = cai*H  \n')\n",
+"I = X * H\n",
+"B = mu_ * (H + I)\n",
+"mur = (1 + I/H)\n",
+"printf('\n Magnetisation is %f A/m.\n Flux density is %f T.\n Relative permeability is %f .',I,B,mur)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 18.3: Calculation_of_Percentage_increase_in_magnetic_induction.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that \n",
+"X = 1.2e-5 // magnetic susceptibility of magnesium\n",
+"// Sample Problem 3 on page no. 18.22\n",
+"printf('\n # PROBLEM 3 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' B = mu_0*H \n')\n",
+"p = 100 * X\n",
+"printf('\n Percentage increase in magnetic induction is %f percent.',p)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 18.4: Calculation_of_Magnetization_and_Magnetic_flux_density.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that \n",
+"X = -0.4e-5 // magnetic susceptibility of material\n",
+"H = 1e4 // magnetic field in A/m\n",
+"mu_ = 4 * %pi * 1e-7 // magnetic permittivity of space\n",
+"// Sample Problem 4 on page no. 18.22\n",
+"printf('\n # PROBLEM 4 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' I = Chi *H \n')\n",
+"I = X * H\n",
+"B = mu_ * (H + I)\n",
+"printf('\n Magnetisation is %f A/m.\n Magnetic flux density is %f T.',I,B)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 18.5: Calculation_of_Permeability_of_aluminium.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that \n",
+"X = 2.3e-5 // magnetic susceptibility of aluminium\n",
+"mu_ = 4 * %pi * 1e-7 // magnetic permeability of space\n",
+"// Sample Problem 5 on page no. 18.23\n",
+"printf('\n # PROBLEM 5 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' mu_r = 1 + Chi \n')\n",
+"mur = 1 + X\n",
+"mu = mu_ * mur\n",
+"printf('\n Permeability of aluminium is %e N/A^2.',mu)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 18.6: Calculation_of_Absolute_permeability_and_Relative_permeability.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that \n",
+"X = 9.4e-2 // magnetic susceptibility\n",
+"mu_ = 4 * %pi * 1e-7 // magnetic permeability of space\n",
+"// Sample Problem 6 on page no. 18.23\n",
+"printf('\n # PROBLEM 6 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' mu_r = 1 + Chi \n')\n",
+"mu_r = 1 + X\n",
+"mu = mu_ * mu_r\n",
+"printf('\n Absolute permeability is %e N/A^2.\n Relative permeability is %f.',mu,mu_r)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 18.7: Calculation_of_Magnetic_susceptibility_and_Relative_permeability.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that \n",
+"mu = 0.126 // maximum value of the permeability in N/A^2\n",
+"mu_ = 4 * %pi * 1e-7 // magnetic permeability of space\n",
+"// Sample Problem 7 on page no. 18.23\n",
+"printf('\n # PROBLEM 7 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' mu_r = 1 + Chi \n')\n",
+"mu_r = mu / mu_\n",
+"X = mu_r - 1\n",
+"printf('\n Magnetic susceptibility is %f .\n Relative permeability is %e',X,mu_r)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 18.8: Calculation_of_Diamagnetic_susceptibility.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that \n",
+"r = 0.6e-10 // radius of the atom\n",
+"N = 28e26 // no. of electron in per m^3\n",
+"mu_ = 4 * %pi * 1e-7 // magnetic permeability of space\n",
+"Z = 2 // atomic no. of helium\n",
+"m = 9.1e-31 // mass of an electron in kg\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"// Sample Problem 8 on page no. 18.24\n",
+"printf('\n # PROBLEM 8 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf('  Chi = mu_0*Z*e^2 *N*R^2 /(6*m) \n')\n",
+"Chi = -(mu_ * Z * N * r^2 * e^2) / (6 * m)\n",
+"printf('\n Diamagnetic susceptibility is %e .',Chi)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 18.9: Calculation_of_Permeability_and_Susceptibility.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that \n",
+"H = 1e3 // magnetisation field in A/m\n",
+"phi = 2e-5 // magnetic flux in Weber\n",
+"a = 0.2e-4 // area of cross section in m^2\n",
+"mu_ = 4 * %pi * 1e-7 // magnetic permeability of space\n",
+"// Sample Problem 9 on page no. 18.24\n",
+"printf('\n # PROBLEM 9 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' mu_r = 1 + Chi \n')\n",
+"B = phi / a\n",
+"mu = B / H\n",
+"X = mu / mu_ - 1\n",
+"printf('\n Permeability is %e N/A^2.\n Susceptibility is %f .',mu,X)"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Engineering_Physics_by_H_K_Malik/19-SUPERCONDUCTIVITY.ipynb b/Engineering_Physics_by_H_K_Malik/19-SUPERCONDUCTIVITY.ipynb
new file mode 100644
index 0000000..0b96756
--- /dev/null
+++ b/Engineering_Physics_by_H_K_Malik/19-SUPERCONDUCTIVITY.ipynb
@@ -0,0 +1,274 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 19: SUPERCONDUCTIVITY"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 19.1: Calculation_of_Penetration_depth.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"T_c = 7.2 // critical temperature in K\n",
+"T = 5.1 // temperature in K\n",
+"lambda_ = 380 // penetration depth at 0 K in A\n",
+"// Sample Problem 1 on page no. 19.13\n",
+"printf('\n # PROBLEM 1 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' lambda = lambda_0 * (1 - (T / T_c)^4)^(-1/2) \n')\n",
+"lambda = lambda_ * (1 - (T / T_c)^4)^(-1/2)\n",
+"printf('\n Penetration depth is %f Angstrom.',lambda)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 19.2: Calculation_of_Transition_temperature_and_Critical_field_at_temperate.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"Hc1 = 1.41e5 // first critical field at 14.1K\n",
+"Hc2 = 4.205e5 // second critical field at 12.9K \n",
+"T1 = 14.11 // temperature in K\n",
+"T2 = 12.9 // temperature in K \n",
+"T = 4.2 // temperature in K\n",
+"lambda_ = 380 // penetration depth at 0 K in A\n",
+"// Sample Problem 2 on page no. 19.13\n",
+"printf('\n # PROBLEM 2 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' H = H_0 * (1 - (T / T_c)^2) \n')\n",
+"Tc = sqrt((Hc2*T1^2 - Hc1*T2^2) / (Hc2 - Hc1))\n",
+"H_ = Hc1 / (1 - (T1 / Tc)^2)\n",
+"Hc = H_ * (1 - (T/Tc)^2)\n",
+"printf('\n Transition temperature is %f K.\n Critical field at temperate at 4.2 k is %e A/m.',Tc,Hc)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 19.3: Calculation_of_Critical_current_density.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that \n",
+"d = 1e-3 // diameter of wire in m\n",
+"T1 = 4.2 // temperature in K\n",
+"T2 = 7.18 // temperature in K\n",
+"H_ = 6.51e4 // critical magnetic field at 0 K\n",
+"// Sample Problem 3 on page no. 19.14\n",
+"printf('\n # PROBLEM 3 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' H = H_0 * (1 - (T / T_c)^2) \n I = 2*pi*r*H \n')\n",
+"r = d / 2\n",
+"Hc = H_ * (1 - (T1 / T2)^2)\n",
+"Jc = (2 * %pi * r * Hc) / (%pi * r^2)\n",
+"printf('\n Critical current density is %e A/m^2',Jc)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 19.4: Calculation_of_Critical_temperature.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"w = 199.5 // isotopic mass of Hg\n",
+"Tc = 4.186 // critical temperature in K \n",
+"w_ = 203.4 // increased isotope mass of Hg\n",
+"// Sample Problem 4 on page no. 19.15\n",
+"printf('\n # PROBLEM 4 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' T_c*M^(1/2) = constant \n')\n",
+"Tc_ = Tc * (w / w_)^(1/2)\n",
+"printf('\n Critical temperature is %f K.',Tc_)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 19.5: Calculation_of_Penetration_depth.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"T_c = 4.2 // critical temperature in K\n",
+"T = 2.9 // temperature in K\n",
+"lambda = 57 // penetration depth at 2.9 K in nm\n",
+"// Sample Problem 5 on page no. 19.15\n",
+"printf('\n # PROBLEM 5 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' lambda_0 = lambda * (1 - (T / T_c)^4)^(1/2) \n')\n",
+"lambda_ = lambda * (1 - (T / T_c)^4)^(1/2)\n",
+"printf('\n Penetration depth at 0 K is %f nm.',lambda_)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 19.6: Calculation_of_Critical_temperature.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"T1 = 2.18 // temperature in first case in K\n",
+"lambda1 = 16 // penetration depth at 2.18 K in nm\n",
+"T2 = 8.1 // temperature in second case in K\n",
+"lambda2 = 96 // penetration depth at 8.1 K in nm\n",
+"// Sample Problem 6 on page no. 19.15\n",
+"printf('\n # PROBLEM 6 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' lambda = lambda_0 * (1 - (T / T_c)^4)^(-1/2) \n')\n",
+"Tc = (((lambda2^2 * T2^4) - (T1^4 * lambda1^2)) / (lambda2^2 - lambda1^2))^(1/4)\n",
+"printf('\n Critical temperature is %f K.',Tc)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 19.7: Calculation_of_Critical_temperature.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"w = 26.91 // isotopic mass of superconducting sample\n",
+"Tc = 1.19 // first critical temperature in K \n",
+"w_ = 32.13 // increased isotope mass of superconducting sample\n",
+"// Sample Problem 7 on page no. 19.16\n",
+"printf('\n # PROBLEM 7 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' T_c*M^(1/2) = constant \n')\n",
+"Tc_ = Tc * (w / w_)^(1/2)\n",
+"printf('\n Critical temperature is %f K.',Tc_)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 19.8: Calculation_of_Energy_gap.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"k = 1.38e-23 // Boltzmann's constant in J/K\n",
+"h = 6.62e-34 // Planck constant in J sec\n",
+"Tc = 4.2 // critical temperature of Hg in K\n",
+"c = 3e8 // speed of light in m/sec \n",
+"// Sample Problem 8 on page no. 19.16\n",
+"printf('\n # PROBLEM 8 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' E = 3 * k * Tc \n')\n",
+"E = 3 * k * Tc\n",
+"lambda = h * c / E\n",
+"printf('\n Energy gap is %e eV.\n Wavelength of photon is %e m.\n From the value of above lambda it is clear that these photons are in the very short wavelength part of the microwave region.',E/1.6e-19,lambda)"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Engineering_Physics_by_H_K_Malik/2-DIFFRACTION.ipynb b/Engineering_Physics_by_H_K_Malik/2-DIFFRACTION.ipynb
new file mode 100644
index 0000000..c15fe0d
--- /dev/null
+++ b/Engineering_Physics_by_H_K_Malik/2-DIFFRACTION.ipynb
@@ -0,0 +1,1314 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 2: DIFFRACTION"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.10: Calculation_of_No_of_zone_of_Fresnel.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 4e-7 // wavelength of light in meter\n",
+"u = 0.2 // distance of object from zone plate in meter\n",
+"v = 0.2 // distance of brightest image from from zone plate in meter \n",
+"r = 0.01 // radius in meter\n",
+"// Sample Problem 10 on page no. 2.41\n",
+"printf('\n # PROBLEM 10 # \n')\n",
+"f = (u * v) / (u + v) // calculation for focal length\n",
+"n = (r^2) / (f * lambda) // calculation for no. of zone of Fresnel\n",
+"printf('\n Standard formula used \n f = (u * v) / (u + v). \n n = (r^2) / (f * lambda).\n ')\n",
+"printf('\n No. of zone of Fresnel = %f',n)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.11: Calculation_of_Distance_of_first_image_from_zone_plate.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 5.893e-7 // wavelength of light in meter\n",
+"d = 2.3e-3 // diameter of the central zone of zone plate in meter\n",
+"u = 6 // distance between point source from zone plate in meter\n",
+"// Sample Problem 11 on page no. 2.42\n",
+"printf('\n # PROBLEM 11 # \n')\n",
+"n = 1 // for central zone\n",
+"f = (d^2) / (4 * lambda * n) // calculation for focal length\n",
+"disp(f)\n",
+"v = (f * u) / (u - f)  // calculation for distance of first image from zone plate\n",
+"printf('\n Standard formula used \n f = (d^2) / (4 * lambda * n). \n v = (f * u) / (u - f). \n ')\n",
+"printf('\n Distance of first image from zone plate = %f meter ',v)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.12: Calculation_of_Principal_focal_length_of_zone_plate.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"R = 2 // radius of curvature in meter\n",
+"// Sample Problem 12 on page no. 2.42\n",
+"printf('\n # PROBLEM 12 # \n')\n",
+"f = R // calculation for principal focal length of zone plate\n",
+"printf('\n Standard formula used \n f = r^2 / lambda. \n r = sqrt(lambda*R). \n ')\n",
+"printf('\n Principal focal length of zone plate = %f meter ',f)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.13: Calculation_of_Angular_spread_of_the_central_maxima.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 5.89e-7 // wavelength of light in meter\n",
+"b = 1e-3 // slit-width in meter\n",
+"// Sample Problem 13 on page no. 2.42\n",
+"printf('\n # PROBLEM 13 # \n')\n",
+"m = 1 // for first minima\n",
+"theta = asin((m * lambda) / b) // calculation for angular spread of the central maxima in radian\n",
+"theta_ = theta * (180 / %pi) // calculation for angular spread of the central maxima in degree\n",
+"printf('\n Standard formula used \n theta = asin((m * lambda) / b).\n')\n",
+"printf('\n Angular spread of the central maxima = %f degree ',2 * theta_)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.14: Calculation_of_Wavelength_of_light.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"d = 1.2 // distance of screen from slit in meter\n",
+"x = 3.7e-3 // distance between first maxima to central maxima in meter\n",
+"b = 2e-4 // slit-width in meter\n",
+"// Sample Problem 14 on page no. 2.43\n",
+"printf('\n # PROBLEM 14 # \n')\n",
+"lambda = (x * b) / d // calculation for wavelength of light\n",
+"printf('\n Standard formula used \n lambda = (x * b) / d.\n')\n",
+"printf('\n Wavelength of light = %e meter. ',lambda)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.15: Calculation_of_Angular_position_of_second_and_third_minima.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 5.5e-7 // wavelength of light in meter\n",
+"b = 2.2e-6 // slit-width in meter\n",
+"// Sample Problem 15 on page no. 2.43\n",
+"printf('\n # PROBLEM 15 # \n')\n",
+"m2 = 2 // for second minima\n",
+"theta2 = asin((m2 * lambda) / b) * (180 / %pi) // calculation for angular position of second minima\n",
+"m3 = 3 // for third minima\n",
+"theta3 = asin((m3 * lambda) / b) * (180 / %pi) // calculation for angular position of third minima\n",
+"printf('\n Standard formula used \n theta = asin((m * lambda) / b) * (180 / pi). \n')\n",
+"printf('\n Angular position of second and third minima = %f , %f degree respectively ',theta2 ,theta3)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.16: Calculation_of_Half_angular_width_of_the_central_bright_maxima.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 5.89e-7 // wavelength of light in meter\n",
+"b = 1.2e-6 // slit-width in meter\n",
+"// Sample Problem 16 on page no. 2.44\n",
+"printf('\n # PROBLEM 16 # \n')\n",
+"m = 1 // for first minima\n",
+"theta = asin((m * lambda) / b) // calculation for half angular width of the central bright maxima in radian\n",
+"theta_ = theta * (180 / %pi) // calculation for half angular width of the central bright maxima in degree\n",
+"printf('\n Standard formula used \n theta = asin((m * lambda) / b).\n')\n",
+"printf('\n Half angular width of the central bright maxima = %f degree ',theta_)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.17: Calculation_of_Slit_width.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 5e-7 // wavelength of light in meter\n",
+"theta = %pi / 6 // half angular width of central maximum in first case in radian\n",
+"theta_ = %pi / 2 // half angular width of central maximum in second case in radian\n",
+"// Sample Problem 17 on page no. 2.44\n",
+"printf('\n # PROBLEM 17 # \n')\n",
+"m = 1 // for first minima\n",
+"b1 = (lambda * m) / sin(theta) // calculation for slit width in first case\n",
+"b2 = (lambda * m) / sin(theta_) // calculation for slit width in second case\n",
+"printf('\n Standard formula used \n b = (lambda * m) / sin(theta). \n')\n",
+"printf('\n Slit width in first case = %e meter. \n Slit width in second case = %e meter',b1,b2)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.18: Calculation_of_Angular_spread_and_linear_width.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 5.89e-7 // wavelength of light in meter\n",
+"d = 1 // distance of screen from slit in meter\n",
+"b = 1e-4 // slit-width in meter\n",
+"// Sample Problem 18 on page no. 2.44\n",
+"printf('\n # PROBLEM 18 # \n')\n",
+"theta = (asin(lambda / b)) * (180 / %pi) // calculation for angular spread\n",
+"x = (2 * d * lambda) / b// calculation for linear width\n",
+"printf('\n Standard formula used \n theta = (asin(lambda / b)) * (180 / pi). \n x = (2 * d * lambda) / b. \n')\n",
+"printf('\n Angular spread = %f degree\n Linear width = %e meter ',theta,x)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.1: Calculation_of_Radius_of_half_period_zone_and_Area_of_half_period_zone.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 5e-7 // wavelength of light in meter\n",
+"d = 1 // distance of wavefront received on the screen from the opening in meter\n",
+"n = 80 // no. of half period zone\n",
+"// Sample Problem 1 on page no. 2.38\n",
+"printf('\n # PROBLEM 1 # \n')\n",
+"Rn = sqrt(n * lambda * d)// calculation for radius of nth half period zone\n",
+"A = %pi * d * lambda// calculation for area of half period zone\n",
+"printf('Standard formula used\n Rn = sqrt(n*d*lambda).\n A = pi*d*lambda.\n')\n",
+"printf('\n Radius of 80th half period zone = %f cm. \n Area of half period zone = %f square cm.',Rn*100,A*10000)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.20: Calculation_of_Angular_width_of_the_central_maxima.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 6e-7 // wavelength of light in meter\n",
+"b = 1.2e-6 // slit-width in meter\n",
+"// Sample Problem 20 on page no. 2.46\n",
+"printf('\n # PROBLEM 20 # \n')\n",
+"m = 1 // for first minima\n",
+"theta = asin((m * lambda) / b) // calculation for angular width of the central maxima in radian\n",
+"theta_ = theta * (180 / %pi) // calculation for angular width of the central maxima in degree\n",
+"printf('\n Standard formula used \n theta = asin((m * lambda) / b). \n')\n",
+"printf('\n Angular width of the central maxima = %f degree ',2 * theta_)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.21: Calculation_of_Separation_of_dark_band.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 4.890e-7 // wavelength of light in meter\n",
+"b = 5e-3 // slit-width in meter\n",
+"f = 0.4 // focal-length of convex lens in meter\n",
+"// Sample Problem 21 on page no. 2.46\n",
+"printf('\n # PROBLEM 21 # \n')\n",
+"m = 1 // for first dark fringe\n",
+"x = (f * m * lambda) / b  \n",
+"n = 1 // for first secondary maxima\n",
+"x_ = ((2 * n + 1) * lambda * f) / (2 * b) \n",
+"delta_x = x_ - x // calculation for separation of dark band \n",
+"printf('\n Standard formula used \n x = (f * m * lambda) / b . \n delta_x = x_ - x. \n')\n",
+"printf('\n Separation of dark band = %e meter.',delta_x)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.22: Calculation_of_Separation_of_dark_band_on_either_side_of_the_central_maximum.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 5.893e-7 // wavelength of light in meter\n",
+"b = 5e-4 // slit-width in meter\n",
+"f = 1 // focal length of convex lens in meter\n",
+"// Sample Problem 22 on page no. 2.47\n",
+"printf('\n # PROBLEM 22 # \n')\n",
+"x = (2 * lambda * f) / b // calculation for Separation of dark band on either side of the cenral maximum\n",
+"printf('Standard formula used \n. \n')\n",
+"printf('\n Separation of dark band on either side of the central maximum = %e meter',x)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.23: Calculation_of_Missing_orders.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"d = 4e-4 // separation between slits in meter\n",
+"b = 8e-5 // slit-width in meter\n",
+"// Sample Problem 23 on page no. 2.47\n",
+"printf('\n # PROBLEM 23 # \n')\n",
+"r = (b + d) / b // calculation for ratio of n with m\n",
+"m1 = 1\n",
+"n1 = r * m1 // calculation for Missing orders \n",
+"m2 = 2\n",
+"n2 = r * m2 // calculation for Missing orders \n",
+"m3 = 3\n",
+"n3 = r * m3 // calculation for Missing orders \n",
+"printf('\n Standard formula used \n r = (b + d) / b. \n n = r * m. \n')\n",
+"printf('\n Missing orders = %d,%d,%d,......',n1,n2,n3)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.24: Calculation_of_Wavelength_of_light_and_Missing_order.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"d = 4e-4 // separation between slits in meter\n",
+"b = 2e-4 // slit-width in meter\n",
+"fringe_width = 2.5e-3 // fringe width in meter\n",
+"D = 1.6 // distance between screen and slits\n",
+"// Sample Problem 24 on page no. 2.47\n",
+"printf('\n # PROBLEM 24 # \n')\n",
+"lambda = (fringe_width * d) / D // calculation for wavelength of light\n",
+"r = (b + d) / b // calculation for ratio of n with m\n",
+"m1 = 1\n",
+"n1 = r * m1 // calculation for missing order\n",
+"m2 = 2\n",
+"n2 = r * m2 // calculation for missing order\n",
+"m3 = 3\n",
+"n3 = r * m3 // calculation for missing order\n",
+"printf('\n Standard formula used \n lambda = (fringe_width * d) / D. \n r = (b + d) / b. \n n = r * m. \n')\n",
+"printf('\n Wavelength of light = %e meter. \n Missing order = %d,%d,%d....',lambda,n1,n2,n3)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.25: Calculation_of_Wavelength_of_light.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"N = 425000 // no. of lines in plane transmission grating per meter\n",
+"theta = %pi / 6 // angle at which second order spectral line is observed in radian\n",
+"n = 2 // order of spectral line\n",
+"// Sample Problem 25 on page no. 2.48\n",
+"printf('\n # PROBLEM 25 # \n')\n",
+"lambda = sin(theta) / (2 * N) // calculation for wavelength of light\n",
+"printf('\n Standard formula used \n lambda = sin(theta) / (2 * N). \n')\n",
+"printf('\n Wavelength of light = %e meter. ',lambda)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.26: Calculation_of_Wavelength_of_light.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"N = 500000 // no. of lines in plane transmission grating per meter\n",
+"theta = %pi / 6 // angle at which second order spectral line is observed in radian\n",
+"n = 2 // order of spectral line\n",
+"// Sample Problem 26 on page no. 2.48\n",
+"printf('\n # PROBLEM 26 # \n')\n",
+"lambda = sin(theta) / (2 * N) // calculation for wavelength of light\n",
+"printf('\n Standard formula used \n lambda = sin(theta) / (2 * N). \n ')\n",
+"printf('\n wavelength of light = %e meter. ',lambda)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.27: Calculation_of_Wavelength_of_light.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda2 = 5.461e-7 // wavelength of  light in second case in meter\n",
+"n1 = 4 // no. of order in first case\n",
+"n2 = 3 // no. of order in second case \n",
+"// Sample Problem 27 on page no. 2.48\n",
+"printf('\n # PROBLEM 27 # \n')\n",
+"lambda1 = (n2 * lambda2) / n1 // calculation for Wavelength of light in first case\n",
+"printf('Standard formula used \n lambda1 = (n2 * lambda2) / n1. \n')\n",
+"printf('\n Wavelength of light in first case = %d A',ceil(lambda1*1e10))"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.28: Calculation_of_No_of_lines_in_per_cm.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 5e-7 // wavelength of light in meter\n",
+"theta = %pi / 6 // angle at which second order spectral line is observed in radian\n",
+"n = 2 // order of spectral line\n",
+"// Sample Problem 28 on page no. 2.49\n",
+"printf('\n # PROBLEM 28 # \n')\n",
+"k = (n * lambda) / sin(theta) // calculation for (b+d)\n",
+"N = 1 / k // calculation for no. of lines in per cm\n",
+"printf('\n Standard formula used \n b+d = (n * lambda) / sin(theta). \n N = 1 / k. \n ')\n",
+"printf('\n No. of lines per cm = %f ',N / 100)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.29: Calculation_of_Angle_of_separation.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda1 = 5.048e-7 // wavelength of light in first case in meter\n",
+"lambda2 = 5.016e-7 // wavelength of light in second case in meter\n",
+"n = 2 // no. of order in first case\n",
+"N = 15000 // no. of lines in grating per inch  \n",
+"// Sample Problem 29 on page no. 2.49\n",
+"printf('\n # PROBLEM 29 # \n')\n",
+"k = 2.54 / 1500000 // in meter\n",
+"theta1 = asin(n * lambda1 / k) * (180 / %pi) // calculation for angle in first case\n",
+"theta2 = asin(n * lambda2 / k) * (180 / %pi) // calculation for angle in second case\n",
+"delta_theta = theta1 - theta2 // calculation for angle of separation\n",
+"printf('\n Standard formula used \n theta = asin(n * lambda / k) * (180 / pi). \n')\n",
+"printf('\n Angle of separation = %f degree',delta_theta)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.2: Calculation_of_Radius_of_half_period_zone.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 6e-7 // wavelength of light in meter\n",
+"f = 0.6 // focal length of convex lens in meter\n",
+"n = 1 // no. of half period zone\n",
+"// Sample Problem 2 on page no. 2.38\n",
+"printf('\n # PROBLEM 2 # \n')\n",
+"Rn = sqrt(n * lambda * f)// calculation for radius of half period zone\n",
+"printf('Standard formula used \n f = Rn^2/(n*lambda)\n')\n",
+"printf('\n Radius of  half period zone = %f mm ',Rn*1000)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.30: Calculation_of_Angle_of_separation.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda1 = 5.89e-7 // wavelength of  light in first case in meter\n",
+"lambda2 = 5.896e-7 // wavelength of  light in second case in meter\n",
+"n = 2 // no. of order in first case\n",
+"N = 600000 // no. of lines in grating per meter  \n",
+"// Sample Problem 30 on page no. 2.50\n",
+"printf('\n # PROBLEM 30 # \n')\n",
+"k = 1 / N // in meter\n",
+"theta1 = asin(n * lambda1 / k) * (180 / %pi) // calculation for angle in first case\n",
+"theta2 = asin(n * lambda2 / k) * (180 / %pi) // calculation for angle in second case\n",
+"delta_theta = theta2 - theta1 // calculation for angle of separation\n",
+"printf('\n Standard formula used \n theta1 = asin(n * lambda1 / k) * (180 / pi). \n ')\n",
+"printf('\n Angle of separation = %f degree',delta_theta)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.31: Calculation_of_No_of_lines_per_cm.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda1 = 5.4e-7 // wavelength of light for nth order in meter\n",
+"lambda2 = 4.05e-7 // wavelength of light for (n+1)th order in meter \n",
+"theta = %pi / 6 // angle of diffraction in radian \n",
+"// Sample Problem 31 on page no. 2.50\n",
+"printf('\n # PROBLEM 31 # \n')\n",
+"k = (lambda1 * lambda2) / ((lambda1 - lambda2) * sin(theta)) // calculation for b+d\n",
+"N = (1 / k) * (0.01) // calculation for no. of lines per cm\n",
+"printf('\n Standard formula used \n b+d = (lambda1 * lambda2) / ((lambda1 - lambda2) * sin(theta)). \n N = (1 / k) * (0.01). \n')\n",
+"printf('\n No. of lines per cm = %d ',N)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.32: Calculation_of_Difference_in_two_wavelength.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"d_theta = 0.01 // angular separation between two wavelengths in radian \n",
+"theta = %pi / 6 // angle of diffraction in radian \n",
+"lambda = 5e-7 // wavelength of light in meter\n",
+"// Sample Problem 32 on page no. 2.51\n",
+"printf('\n # PROBLEM 32 # \n')\n",
+"d_lambda = (lambda * cos(theta) * d_theta) / sin(theta) // calculation for difference in two waveligth\n",
+"printf('Standard formula used \n d_lambda = (lambda * cos(theta) * d_theta) / sin(theta). \n\n')\n",
+"printf('\n Difference in two wavelength = %e meter ',d_lambda)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.33: Calculation_of_Order_of_spectrum.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"N = 2620 // no. of lines in plane transmission grating per inch\n",
+"lambda = 5e-7 // wavelength of incident radiation in meter\n",
+"// Sample Problem 33 on page no. 2.51\n",
+"printf('\n # PROBLEM 33 # \n')\n",
+"k = 2.54 / N * 1 / 100 // calculation for b+d in meter\n",
+"n = k / lambda // calculation for order of spectrum\n",
+"printf('\n Standard formula used \n n = k / lambda ')\n",
+"printf('\n Order of spectrum = %d',n)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.34: Calculation_of_Order_of_spectrum.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"N = 500000 // no. of lines in plane transmission grating per meter\n",
+"lambda = 5e-7 // wavelength of incident radiation in meter\n",
+"// Sample Problem 34 on page no. 2.51\n",
+"printf('\n # PROBLEM 34 # \n')\n",
+"k = 1 / N // calculation for b+d in meter\n",
+"n = k / lambda // calculation for order of spectrum \n",
+"printf('\n Standard formula used \n k = 1 / N. \n n = k / lambda. \n')\n",
+"printf('\n Order of spectrum = %d',n)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.35: Calculation_of_Observed_order.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"N = 400000 // no. of lines in plane transmission grating per meter\n",
+"lambda1 = 4e-7 // wavelength of light in first case in meter\n",
+"lambda2 = 7e-7 // wavelength of light in second case in meter\n",
+"// Sample Problem 35 on page no. 2.52\n",
+"printf('\n # PROBLEM 35 # \n')\n",
+"n1 = 1 / (N * lambda1) // calculation for Observed order in first case\n",
+"n2 = 1 / (N * lambda2) // calculation for Observed order in second case\n",
+"printf('Standard formula used \n n = 1 / (N * lambda). \n')\n",
+"printf('\n Observed order = %d,%d',n1,n2)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.36: Calculation_of_Dispersive_power.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"N = 400000 // no. of lines in grating per meter\n",
+"lambda = 5e-7 // wavelength of incident radiation in meter\n",
+"n = 3 // no. of order\n",
+"// Sample Problem 36 on page no. 2.52\n",
+"printf('\n # PROBLEM 36 # \n')\n",
+"p = (n * N) / (sqrt(1 - (N * n * lambda)))// dispersive power (p) = d(theta)/d(lambda)\n",
+"printf('\n Standard formula used \n p = (n * N) / (sqrt(1 - (N * n * lambda))). \n')\n",
+"printf('\n Dispersive power = %e rad/m',p)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.37: Calculation_of_Minimum_no_of_lines_in_grating.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"n = 2 // no. of order\n",
+"lambda1 = 5.89e-7 // wavelength of light in first case in meter\n",
+"lambda2 = 5.896e-7 // wavelength of light in second case in meter\n",
+"// Sample Problem 37 on page no. 2.52\n",
+"printf('\n # PROBLEM 37 # \n')\n",
+"N = lambda1 / (n * (lambda2 - lambda1)) // calculation for minimum no. of lines in grating \n",
+"printf('\n Standard formula used \n N = lambda1 / (n * (lambda2 - lambda1)). \n') \n",
+"printf('\n Minimum no. of lines in grating = %f,',N)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.38: Calculation_of_Minimum_no_of_lines_in_grating.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"n = 1 // no. of order\n",
+"lambda1 = 5.89e-7 // wavelength of light in first case in meter\n",
+"lambda2 = 5.896e-7 // wavelength of light in second case in meter\n",
+"// Sample Problem 38 on page no. 2.53\n",
+"printf('\n # PROBLEM 38 # \n')\n",
+"N = lambda1 / (n * (lambda2 - lambda1)) // calculation for minimum no. of lines in grating\n",
+"printf('Standard formula used \n lambda/d(lambda)=n*N. \n')\n",
+"printf('\n Minimum no. of lines in grating = %f,',N)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.39: Calculation_of_Grating_space_and_Total_width_of_ruled_surface.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"n = 3 // no. of order\n",
+"theta = %pi / 6 // view angle of third order in radian\n",
+"lambda1 = 5.89e-7 // min. wavelength of light in meter\n",
+"lambda2 = 5.896e-7 // max.wavelength of light in meter\n",
+"// Sample Problem 39 on page no. 2.53\n",
+"printf('\n # PROBLEM 39 # \n')\n",
+"mean_lambda = (lambda1 + lambda2) / 2 // calculation for mean wavelength\n",
+"s = (n * mean_lambda) / sin(theta) // calculation for grating space b+d\n",
+"N = lambda1 / (n * (lambda2 - lambda1)) // calculation for minimum no. of lines in grating\n",
+"printf('\n Standard formula used \n mean_lambda = (lambda1 + lambda2) / 2. \n s = (n * mean_lambda) / sin(theta). \n N = lambda1 / (n * (lambda2 - lambda1)). \n')\n",
+"printf('\n Grating space = %e meter. \n Total width of ruled surface = %e meter. ',s,s * N)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.3: Calculation_of_Radius_of_half_period_zone.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 5e-7 // wavelength of light in meter\n",
+"d = 0.3 // distance of wavefront received on screen from the opening in meter\n",
+"// Sample Problem 3 on page no. 2.38\n",
+"printf('\n # PROBLEM 3 # \n')\n",
+"n = 1 // no. of half period zone\n",
+"Rn = sqrt(n * lambda * d) // because at maxima intensity is four time the individual intensity of light\n",
+"printf('Standard formula used \n r = sqrt(d*lambda)\n')\n",
+"printf('\n Radius of 80th half period zone = %f mm. ',Rn*1000)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.40: Calculation_of_The_separation_of_two_points_on_moon.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 5.5e-7 // wavelength of light in meter\n",
+"a = 5 // diameter of objective lens of telescope in meter\n",
+"R = 3.8e8 // distance of moon in meter\n",
+"// Sample Problem 40 on page no. 2.53\n",
+"printf('\n # PROBLEM 40 # \n')\n",
+"theta = (1.22 * lambda) / a // calculation for angle \n",
+"x = (R * theta) // calculation for the separation of two points on moon\n",
+"printf('\n Standard formula used \n theta = (1.22 * lambda) / a. \n x = (R * theta). \n')\n",
+"printf('\n The separation of two points on moon = %f meter',x)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.41: Calculation_of_Diameter_of_telescope_objective.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 5e-7 // wavelength of light in meter\n",
+"theta = (1e-3) * (%pi / 180) // separation angle of stars in radian\n",
+"// Sample Problem 41 on page no. 2.54\n",
+"printf('\n # PROBLEM 41 # \n')\n",
+"a = (1.22 * lambda) / theta // calculation for diameter of telescope objective\n",
+"printf('\n Standard formula used \n a = (1.22 * lambda) / theta. \n')\n",
+"printf('\n Diameter of telescope objective = %f meter',a)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.42: Calculation_of_Diameter_of_telescope_objective.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 6e-7 // wavelength of light in meter\n",
+"theta = 2.44e-6 // separation angle of stars in radian\n",
+"// Sample Problem 42 on page no. 2.54\n",
+"printf('\n # PROBLEM 42 # \n')\n",
+"a = (1.22 * lambda) / theta // calculation for diameter of telescope objective\n",
+"printf('\n Standard formula used \n a = (1.22 * lambda) / theta. \n')\n",
+"printf('\n Diameter of telescope objective = %f meter',a)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.43: Calculation_of_Max_distance_of_pin_holes_from_microscope.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 5.5e-7 // wavelength of light in meter\n",
+"a = 0.004 // diameter of objective lens of telescope in meter\n",
+"x = 1.5e-3 // distance between two pin holes in meter\n",
+"// Sample Problem 43 on page no. 2.54\n",
+"printf('\n # PROBLEM 43 # \n')\n",
+"theta = (1.22 * lambda) / a // calculation for angle  \n",
+"R = x / theta // calculation for max. distance of pin holes from microscope\n",
+"printf('\n Standard formula used \n theta = (1.22 * lambda) / a. \n R = x / theta. \n ')\n",
+"printf('\n Max. distance of pin holes from microscope = %f meter',R)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.44: Calculation_of_The_resolving_limit_of_microscope.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 5.5e-7 // wavelength of light in meter\n",
+"theta = %pi / 6 // semi-angle of cone in radian\n",
+"// Sample Problem 44 on page no. 2.55\n",
+"printf('\n # PROBLEM 44 # \n')\n",
+"d = (1.22 * lambda) / (2 * sin(theta)) // calculation for the resolving limit of microscope \n",
+"printf('Standard formula used \n d*sin(theta)= 1.22*lamda. \n')\n",
+"printf('\n The resolving limit of microscope = %e meter',d)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.45: Calculation_of_Numerical_aperture_of_objective.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 5.461e-7 // wavelength of light in meter\n",
+"d = 4e-7 // separation between objects in meter\n",
+"// Sample Problem 45 on page no. 2.55\n",
+"printf('\n # PROBLEM 45 # \n')\n",
+"NA = (1.22 * lambda) / (2 * d) // calculation for numerical aperture of objective \n",
+"printf('\n Standard formula used \n NA = (1.22 * lambda) / (2 * d). \n')\n",
+"printf('\n Numerical aperture of objective = %f',NA)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.4: Calculation_of_No_of_half_period_zone.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 6e-7 // wavelength of light in meter\n",
+"d = 0.5 // distance of observation point from circular opening in meter\n",
+"r1 = 2e-3 // radius of circular opening in first case in meter\n",
+"r2 = 2e-2 // radius of circular opening in second case in meter \n",
+"// Sample Problem 4 on page no. 2.39\n",
+"printf('\n # PROBLEM 4 # \n')\n",
+"n1 = (r1^2) / (d * lambda) // calculation for no. of half period zone in first case \n",
+"n2 = (r2^2) / (d * lambda) // calculation for no. of half period zone in second case\n",
+"printf('\n Standard formula used \n n = (r^2) / (d * lambda) \n')\n",
+"printf('\n No. of half period zone in first case = %d \n no. of half period zone in second case = %d ',n1,n2)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.5: Calculation_of_Distance_of_screen_from_opening.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 5e-7 // wavelength of light in meter\n",
+"d = 1e-3 // diameter of the first ring of zone plate in meter\n",
+"// Sample Problem 5 on page no. 2.39\n",
+"printf('\n # PROBLEM 5 # \n')\n",
+"n = 1 // no. of half period zone\n",
+"D = (d^2) / (4 * lambda * n) // calculation for distance of screen from opening\n",
+"printf('\n Standard formula used \n D = (d^2) / (4 * lambda * n). \n')\n",
+"printf('\n Distance of screen from opening = %f meter ',D)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.6: Calculation_of_Radius_of_first_and_second_and_third_half_period_zone.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 5.893e-7 // wavelength of light in meter\n",
+"f = 1 // focal-length of convex lens in meter\n",
+"n1 = 1 // no. of first half period zone\n",
+"n2 = 3 // no. of second half period zone\n",
+"n3 = 5 // no. of third half period zone\n",
+"// Sample Problem 6 on page no. 2.40\n",
+"printf('\n # PROBLEM 6 # \n')\n",
+"R1 = sqrt(n1 * lambda * f) // calculation for Radius of first half period zone\n",
+"R2 = sqrt(n2 * lambda * f) // calculation for Radius of second half period zone\n",
+"R3 = sqrt(n3 * lambda * f) // calculation for Radius of third half period zone\n",
+"printf('Standard formula used \n R = sqrt(f*n*lambda)\n')\n",
+"printf('\n Radius of first ,second and third half period zone = %e,%e and %e meter. ',R1,R2,R3)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.7: Calculation_of_Radius_of_half_period_zone.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 5e-7 // wavelength of light in meter\n",
+"f = 0.2 // focal length of convex lens in meter\n",
+"n = 10 // no. of half period zone\n",
+"// Sample Problem 7 on page no. 2.40\n",
+"printf('\n # PROBLEM 7 # \n')\n",
+"Rn = sqrt(n * lambda * f) // calculation for radius of 10th half period zone\n",
+"printf('\n Standard formula used \n Rn = sqrt(n * lambda * f).\n')\n",
+"printf('\n Radius of 10th half period zone = %f mm. ',Rn*1000)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.8: Calculation_of_Focal_length_and_Power_and_Diameter_of_first_zone.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 5.89e-7 // wavelength of light in meter\n",
+"d1 = 1 // distance of wavefront recieved on the screen from the opening in first side in meter\n",
+"d2 = 2 // distance of wavefront recieved on the screen from the opening in other side in meter\n",
+"// Sample Problem 8 on page no. 2.40\n",
+"printf('\n # PROBLEM 8 # \n')\n",
+"f = (d1 * d2) / (d1 + d2)\n",
+"p = 1 / f // beacause zone plate act as a convex lens\n",
+"n = 1 // for first zone\n",
+"Rn = sqrt(n * lambda * f) // calculation for radius of first zone\n",
+"Dn = 2 * Rn // calculation for diameter of first zone\n",
+"printf('\n Standard formula used \n ')\n",
+"printf('\n Focal length = %f meter. \n Power = %f D. \n Diameter of first zone = %f mm. ',f,p,Dn*1000)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 2.9: Calculation_of_Focal_length.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda1 = 6e-7 // wavelength of first light in meter\n",
+"lambda2 = 5e-7 // wavelength of second light in meter\n",
+"f1 = 1 // focal length in first case in meter \n",
+"// Sample Problem 9 on page no. 2.41\n",
+"printf('\n # PROBLEM 9 # \n')\n",
+"f2 = (lambda1 * f1) / lambda2 // calculation for focal length in second case\n",
+"printf('\n Standard formula used \n f2 = (lambda1 * f1) / lambda2')\n",
+"printf('\n Focal length in second case = %f meter',f2)"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Engineering_Physics_by_H_K_Malik/20-X_RAY.ipynb b/Engineering_Physics_by_H_K_Malik/20-X_RAY.ipynb
new file mode 100644
index 0000000..fbba329
--- /dev/null
+++ b/Engineering_Physics_by_H_K_Malik/20-X_RAY.ipynb
@@ -0,0 +1,597 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 20: X RAY"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 20.10: Calculation_of_Applied_voltage.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda1 = 40e-12 // minimum wavelength in first case in m\n",
+"lambda2 = 1e-10 // minimum wavelength in second case in m\n",
+"// Sample Problem 10 on page no. 20.10\n",
+"printf('\n # PROBLEM 10 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf('lambda_min = 12400/V \n')\n",
+"V1 = 12400e-10 / lambda1\n",
+"V2 = 12400e-10 / lambda2\n",
+"printf('\n Applied voltage to get wavelength of %e meter is %f KV. \n Applied voltage to get wavelength of %e meter is %f KV.',lambda1,V1/10^3,lambda2,V2/10^3)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 20.11: Calculation_of_Planck_constant.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"V1 = 44e3 // voltage in first case in V\n",
+"V2 = 50e3 // voltage in second case in V\n",
+"lambda1 = 0.284e-10 // shortest wavelength in first case in m\n",
+"lambda2 = 0.248e-10 // shortest wavelength in second case in m\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"c = 3e8 // speed of light in m/sec\n",
+"// Sample Problem 11 on page no. 20.10\n",
+"printf('\n # PROBLEM 11 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' h*c/Lambda = eV \n')\n",
+"h1 = e * V1 * lambda1 / c\n",
+"h2 = e * V2 * lambda2 / c\n",
+"printf('\n Planck constant is %e J sec if shortest wavelength is %e m .\n Planck constant is %e Jsec if shortest wavelength is %e m. ',h1,lambda1,h2,lambda2)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 20.12: Calculation_of_Excitation_potential.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 1e-11 // K-absorption limit for uranium in m\n",
+"// Sample Problem 12 on page no. 20.10\n",
+"printf('\n # PROBLEM 12 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf('lambda_min = 12400/V \n')\n",
+"V = 12400e-10 / lambda\n",
+"printf('\n Excitation potential is %d kV.',V/10^3)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 20.13: Calculation_of_the_value_of_the_ratio_of_plank_constant_and_charge_of_electron.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 1.4e-11 // K-absorption edge for lead in m\n",
+"V = 88.6e3 // minimum voltage required for producing k-lines in V\n",
+"c = 3e8 // speed of light in m/sec\n",
+"// Sample Problem 13 on page no. 20.11\n",
+"printf('\n # PROBLEM 13 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' h*c/Lambda = eV \n')\n",
+"r = V * lambda / c\n",
+"printf('\n The value of the ratio of h/e = %e Jsec/C.',r)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 20.14: Calculation_of_Wavelength_of_K_line.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"Z = 92 // atomic no. of atom\n",
+"Rh = 1.1e5 // Rydberg constant in cm^-1\n",
+"c = 3e8 // speed of light in m/sec\n",
+"// Sample Problem 14 on page no. 20.11\n",
+"printf('\n # PROBLEM 14 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' Moseley Law \n ')\n",
+"lambda = 1 / (Rh *(Z-1)^2 * (1 - (1 / 2^2)))\n",
+"printf('\n Wavelength of K line = %f A',lambda*1e8)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 20.15: Calculation_of_Wavelength.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"Z = 42 // atomic no. of Mo\n",
+"lambda = 0.71e-10 // wavelength in m\n",
+"Z_ = 29 // atomic no. of Cu\n",
+"// Sample Problem 15 on page no. 20.11\n",
+"printf('\n # PROBLEM 15 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' nu = a*(Z-b)^2 ........Moseley law \n')\n",
+"lambda_ = (Z-1)^2 * lambda / (Z_-1)^2\n",
+"printf('\n Wavelength of the corresponding radiation of Cu is %f Angstrom.',lambda_*1e10)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 20.16: Calculation_of_Wavelength_of_xray.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"Z = 79 // atomic no. of element\n",
+"b = 1 // a constant\n",
+"a = 2.468e15 // a constant in per sec\n",
+"c = 3e8 // speed of light in m/sec\n",
+"// Sample Problem 16 on page no. 20.12\n",
+"printf('\n # PROBLEM 16 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' nu = a*(Z-b)^2 ........Moseley law \n')\n",
+"f = a * (Z - b)^2\n",
+"lambda = c / f\n",
+"printf('\n Wavelength of x-ray is %f Angstrom.',lambda*1e10)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 20.17: Calculation_of_Ionization_potential_of_K_shell_electron_of_Cu.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"Z = 29 // atomic no. of Cu\n",
+"R = 1.097e7 // Rydberg constant in m^-1\n",
+"c = 3e8 // speed of light in m/sec\n",
+"h = 6.62e-34 // Planck constant in J sec\n",
+"// Sample Problem 17 on page no. 20.12\n",
+"printf('\n # PROBLEM 17 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' nu = a*(Z-b)^2 ........Moseley law \n')\n",
+"f = 3/4 * (R * c) * (Z-1)^2\n",
+"E = h * f / 1.6e-16\n",
+"E_L = 0.931 // let E_L = 0.931 KeV\n",
+"E_ = E + E_L\n",
+"printf('\n Ionization potential of K-shell electron of Cu is %f keV.',E_)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 20.18: Calculation_of_Frequency_of_k_line.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"Z = 79 // atomic no. of anticathode\n",
+"R = 1.097e7 // Rydberg constant in m^-1\n",
+"c = 3e8 // speed of light in m/sec\n",
+"// Sample Problem 18 on page no. 20.13\n",
+"printf('\n # PROBLEM 18 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf(' nu = a*(Z-b)^2 ........Moseley law \n')\n",
+"f = 3/4 * (R * c) * (Z-1)^2\n",
+"printf('\n Frequency of k line is %e Hz.',f)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 20.19: Calculation_of_Energy_and_Wavelength_of_xray.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"Z = 27 // atomic no. of Co\n",
+"R = 1.097e7 // Rydberg constant in m^-1\n",
+"c = 3e8 // speed of light in m/sec\n",
+"h = 6.62e-34 // Planck constant in J sec\n",
+"// Sample Problem 19 on page no. 20.13\n",
+"printf('\n # PROBLEM 19 # \n')\n",
+"printf('Standard formula used \n')\n",
+"printf(' nu = a*(Z-b)^2 ........Moseley law \n')\n",
+"f = 3/4 * (R * c) * (Z-1)^2\n",
+"E = h * f\n",
+"lambda = c / f\n",
+"printf('\n Energy is %f keV.\n Wavelength of x-ray is %f Angstrom.',E / 1.6e-16,lambda*1e10)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 20.1: Calculation_of_Max_speed_and_Shortest_wavelength.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"V1 = 40e3 // voltage in first case in V\n",
+"V2 = 20e3 // voltage in second case in V\n",
+"V3 = 100e3 // voltage in second in V\n",
+"// Sample Problem 1 on page no. 20.7\n",
+"printf('\n # PROBLEM 1 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf('1/2*m*v^2 = eV \n')\n",
+"v1 = 0.593e6 * sqrt(V1)\n",
+"lambda1 = 12400 / V1\n",
+"v2 = 0.593e6 * sqrt(V2)\n",
+"lambda2 = 12400 / V2\n",
+"v3 = 0.593e6 * sqrt(V3)\n",
+"lambda3 = 12400 / V3\n",
+"printf('\n Max. speed of electrons at %d Volts is %e m/sec.\n Max. speed of electrons at %d Volts is %e m/sec./sec.\n Max. speed of electrons at %d Volts is %e m/sec. \n Shortest wavelength of x-ray = %f Angstrom.\n Shortest wavelength of x-ray = %f Angstrom.\n Shortest wavelength of x-ray = %f Angstrom.',V1,v1,V2,v2,V3,v3,lambda1,lambda2,lambda3)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 20.2: Calculation_of_Planck_constant.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"V = 30e3 // voltage in V\n",
+"lambda_min = 0.414e-10 // shortest wavelength in m\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"c = 3e8 // speed of light in m/sec\n",
+"// Sample Problem 2 on page no. 20.7\n",
+"printf('\n # PROBLEM 2 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf('h*c/lambda = eV \n')\n",
+"h = (e * V * lambda_min) / c\n",
+"printf('\n Planck constant is %e J sec.',h)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 20.3: Calculation_of_Minimum_wavelength.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"V = 25e3 // voltage in V\n",
+"// Sample Problem 3 on page no. 20.8\n",
+"printf('\n # PROBLEM 3 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf('Lambda_min = 12400/V \n')\n",
+"lambda_min = 12400 / V\n",
+"printf('\n Minimum wavelength of x-ray is %f Angstrom.',lambda_min)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 20.4: Calculation_of_Maximum_speed_of_electron.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"V = 13.6e3 // voltage in V\n",
+"// Sample Problem 4 on page no. 20.8\n",
+"printf('\n # PROBLEM 4 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf('1/2*m*v^2 = eV \n')\n",
+"v = 0.593e6*sqrt(V)\n",
+"printf('\n Maximum speed of electron is %e m/sec.',v)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 20.5: Calculation_of_Velocity_of_electron.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"V = 10e3 // voltage in V\n",
+"i = 2e-3 // current in amp\n",
+"// Sample Problem 5 on page no. 20.8\n",
+"printf('\n # PROBLEM 5 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf('1/2*m*v^2 = eV \n')\n",
+"v = 0.593e6*sqrt(V)\n",
+"printf('\n Velocity of electron is %e m/sec.',v)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 20.6: Calculation_of_Highest_frequency_and_Minimum_wavelength.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"V = 9.8e3 // voltage in V\n",
+"i = 2e-3 // current in amp\n",
+"c = 3e8 // speed of light in m/sec\n",
+"// Sample Problem 6 on page no. 20.8\n",
+"printf('\n # PROBLEM 6 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf('h*c/lambda = eV \n')\n",
+"lambda = 12400 / V\n",
+"f = c / lambda\n",
+"printf('\n Highest frequency is %e Hz.\n Minimum wavelength is %f Angstrom.',f,lambda)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 20.7: Calculation_of_Number_of_electrons_striking_the_target_and_Speed_of_electrons.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"V = 12.4e3 // voltage in V\n",
+"i = 2e-3 // current in amp\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"// Sample Problem 7 on page no. 20.9\n",
+"printf('\n # PROBLEM 7 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf('I = ne \n 1/2*m*v^2 = eV \n')\n",
+"n = i / e\n",
+"v = 0.593e6*sqrt(V)\n",
+"printf('\n Number of electrons striking the target per sec is %e.\n Speed of electrons is %e m/sec.',n,v)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 20.8: Calculation_of_Number_of_electrons_striking_the_anode_and_Minimum_wavelength.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"V = 10e3 // voltage in V\n",
+"i = 15e-3 // current in amp\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"// Sample Problem 8 on page no. 20.9\n",
+"printf('\n # PROBLEM 8 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf('I = ne \n 1/2*m*v^2 = eV \n')\n",
+"n = i / e\n",
+"lambda = 12400 / V \n",
+"printf('\n Number of electrons striking the anode per sec is %e.\n Minimum wavelength produced  is %f Angstrom.',n,lambda)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 20.9: Calculation_of_Number_of_electrons_striking_the_anode.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"V = 50e3 // voltage in V\n",
+"i = 1e-3 // current in amp\n",
+"e = 1.6e-19 // charge on an electron in C\n",
+"// Sample Problem 9 on page no. 20.9\n",
+"printf('\n # PROBLEM 9 # \n')\n",
+"printf('Standard formula used \n ')\n",
+"printf('I = ne \n')\n",
+"n = i / e\n",
+"printf('\n Number of electrons striking the anode per sec is %e.',n)"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Engineering_Physics_by_H_K_Malik/22-NANOPHYSICS.ipynb b/Engineering_Physics_by_H_K_Malik/22-NANOPHYSICS.ipynb
new file mode 100644
index 0000000..a1646a3
--- /dev/null
+++ b/Engineering_Physics_by_H_K_Malik/22-NANOPHYSICS.ipynb
@@ -0,0 +1,61 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 22: NANOPHYSICS"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 22.1: EX22_1.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"d = 12e-6 // diameter in m\n",
+"d_ = 90e-9 // diameter of nanoparticle in m\n",
+"// Sample Problem 1 on page no. 22.13\n",
+"printf('\n # PROBLEM 1 # \n')\n",
+"r = d / 2\n",
+"r_ = d_ / 2\n",
+"k = r / 3\n",
+"k_ = r_ / 3\n",
+"R = k_ / k\n",
+"printf('\n The ratio of the value of Nb/Ns of spherical particle and nanoparticle = %e .',R)"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Engineering_Physics_by_H_K_Malik/3-POLARISATION.ipynb b/Engineering_Physics_by_H_K_Malik/3-POLARISATION.ipynb
new file mode 100644
index 0000000..2c3ad44
--- /dev/null
+++ b/Engineering_Physics_by_H_K_Malik/3-POLARISATION.ipynb
@@ -0,0 +1,764 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 3: POLARISATION"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.10: Calculation_of_Percentage_reduction_in_intensity_of_light.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"theta1 = %pi / 6 // angle between Nicole prisms in first case in radian\n",
+"theta2 = %pi / 4 // angle between Nicole prisms in second case in radian\n",
+"theta3 = %pi / 3 // angle between Nicole prisms in third case in radian\n",
+"theta4 = %pi / 2 // angle between Nicole prisms in fourth case in radian\n",
+"// Sample Problem 10 on page no. 3.26\n",
+"printf('\n # PROBLEM 10 # \n')\n",
+"I1 = (1 - (cos(theta1))^2) * 100\n",
+"I2 = (1 - (cos(theta2))^2) * 100\n",
+"I3 = (1 - (cos(theta3))^2) * 100\n",
+"I4 = (1 - (cos(theta4))^2) * 100\n",
+" // calculation for percentage reduction in intensity of ligth\n",
+" printf('\n Standard formula used \n I = (1 - (cos(theta))^2) * 100. \n')\n",
+"printf('\n Percentage reduction in intensity of ligth-\n(i)%f per\n(ii)%f per\n(iii)%f per\n(iv)%f per',I1,I2,I3,I4)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.11: Calculation_of_Angle_between_the_Nicols.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"i1 = 1 / 2 // reduced intensity ratio in first case\n",
+"i2 = 1 / 4 // reduced intensity ratio in second case\n",
+"// Sample Problem 11 on page no. 3.27\n",
+"printf('\n # PROBLEM 11 # \n')\n",
+"theta1 = acos(sqrt(i1)) * (180 / %pi)// calculation for angle between nicols in first case \n",
+"theta2 = acos(sqrt(i2)) * (180 / %pi)// calculation for angle between nicols in second case\n",
+"printf('Standard formula used \n I=I_cos(theta)^2\n')\n",
+"printf('\n Angle between the Nicols in first case = %f degree\n And in second case = %f degree',theta1,theta2)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.12: Calculation_of_Thickness_of_half_wave_plate_of_quartz.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 5e-7 // wavelength of light in meter\n",
+"mu_e = 1.553 // refractive index for extraordinary light\n",
+"mu_o = 1.544 // refractive index for ordinary light\n",
+"// Sample Problem 12 on page no. 3.27\n",
+"printf('\n # PROBLEM 12 # \n')\n",
+"t = lambda / (2 * (mu_e - mu_o)) // calculation for thickness of half-wave plate of quartz\n",
+"printf('\n Standard formula used \n t = lambda / (2 * (mu_e - mu_o)). \n')\n",
+"printf('\n Thickness of half-wave plate of quartz = %e meter',t)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.13: Calculation_of_Thickness_of_quartz_plate.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 5.893e-7 // wavelength of light in meter\n",
+"mu_e = 1.533 // refractive index for extraordinary light\n",
+"mu_o = 1.554 // refractive index for ordinary light\n",
+"// Sample Problem 13 on page no. 3.27\n",
+"printf('\n # PROBLEM 13 # \n')\n",
+"t = lambda / (4 * (mu_o - mu_e)) // calculation for thickness of quartz plate\n",
+"printf('\n Standard formula used \n t = lambda / (4 * (mu_o - mu_e)). \n ')\n",
+"printf('\n Thickness of quartz plate  = %e meter',t)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.14: Calculation_of_Thickness_quartz_plate.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 5.89e-7 // wavelength of light in meter\n",
+"mu_e1 = 1.5 // refractive index for extraordinary light in first case\n",
+"mu_o1 = 1.55 // refractive index for ordinary light in first case\n",
+"mu_e2 = 1.57 // refractive index for extraordinary light in second case\n",
+"mu_o2 = 1.55 // refractive index for ordinary light in second case\n",
+"// Sample Problem 14 on page no. 3.28\n",
+"printf('\n # PROBLEM 14 # \n')\n",
+"t1 = lambda / (4 * (mu_o1 - mu_e1))\n",
+"t2 = lambda / (4 * (mu_e2 - mu_o2))\n",
+" // calculation for thickness of plate of quartz\n",
+" printf('\n Standard formula used \n t = lambda / (4 * (mu_o - mu_e)) ')\n",
+"printf('\n Thickness of plate of quartz in first case = %e meter,\n And thickness of plate of quartz in second case = %e meter',t1,t2)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.15: Calculation_of_Thickness_of_calcite_plate.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 5.89e-7 // wavelength of light in meter\n",
+"mu_e = 1.486 // refractive index for extraordinary light\n",
+"mu_o = 1.658 // refractive index for ordinary light\n",
+"// Sample Problem 15 on page no. 3.28\n",
+"printf('\n # PROBLEM 15 # \n')\n",
+"t = lambda / (4 * (mu_o - mu_e)) // calculation for thickness of calcite plate \n",
+"printf('\n Standard formula used \n t = lambda / (4 * (mu_o - mu_e)). \n')\n",
+"printf('\n Thickness of calcite plate  = %e meter',t)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.16: Calculation_of_Thickness_of_quartz_plate.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 5e-7 // wavelength of light in meter\n",
+"mu_e = 1.5533 // refractive index for extraordinary light\n",
+"mu_o = 1.5442 // refractive index for ordinary light\n",
+"// Sample Problem 16 on page no. 3.28\n",
+"printf('\n # PROBLEM 16 # \n')\n",
+"t = lambda / (4 * (mu_e - mu_o)) // calculation for thickness of quartz plate\n",
+"printf('\n Standard formula used \n t = lambda / (4 * (mu_e - mu_o)). \n')\n",
+"printf('\n Thickness of quartz plate  = %e meter',t)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.17: Calculation_of_Thickness_of_quartz_plate.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 5.89e-7 // wavelength of light in meter\n",
+"mu_e = 1.54 // refractive index for extraordinary light\n",
+"mu_o = 1.55 // refractive index for ordinary light\n",
+"// Sample Problem 17 on page no. 3.28\n",
+"printf('\n # PROBLEM 17 # \n')\n",
+"t = lambda / (4 * (mu_o - mu_e)) // calculation for thickness of quartz plate\n",
+"printf('\n Standard formula used \n t = lambda / (4 * (mu_o - mu_e))')\n",
+"printf('\n Thickness of quartz plate  = %e meter',t)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.18: Calculation_of_Thickness_of_quartz_plate.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 5.89e-7 // wavelength of light in meter\n",
+"mu_e = 1.553 // refractive index for extraordinary light\n",
+"mu_o = 1.544 // refractive index for ordinary light\n",
+"// Sample Problem 18 on page no. 3.28\n",
+"printf('\n # PROBLEM 18 # \n')\n",
+"t = lambda / (4 * (mu_e - mu_o)) // calculation for thickness of quartz plate\n",
+"printf('\n Standard formula used \n t = lambda / (4 * (mu_e - mu_o)).\n')\n",
+"printf('\n Thickness of quartz plate  = %e meter',t)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.19: Calculation_of_Thickness_of_quartz_plate.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"mu_e = 1.5442 // refractive index for extraordinary light\n",
+"mu_o = 1.5533 // refractive index for ordinary light\n",
+"lambda = 5e-7 // wavelength of plane polarized light in meter\n",
+"// Sample Problem 19 on page no. 3.29\n",
+"printf('\n # PROBLEM 19 # \n')\n",
+"t = lambda / (2 * (mu_o - mu_e))// calculation for thickness of quartz plate\n",
+"printf('Standard formula used \n t=lambda/4(mu_o-mu_e)\n')\n",
+"printf('\n Thickness of quartz plate  = %e meter',t)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.1: Calculation_of_Brewster_angle_and_Angle_of_refraction.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"mu = 1.5 // refractive index of glass\n",
+"// Sample Problem 1 on page no. 3.23\n",
+"printf('\n # PROBLEM 1 # \n')\n",
+"Ip = atan(mu) * (180 / %pi) // by brewster's law\n",
+"r = 90 - Ip // calculation for angle of refraction\n",
+"printf('Standard formula used \n mu=tan(Ip)\n')\n",
+"printf('\n Brewster angle = %f degree\n Angle of refraction = %f degree',Ip,r)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.20: Calculation_of_Concentration_of_sugar_solution.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"theta = 10 // rotation of plane of polarization in degree\n",
+"s = 60 // specific rotation of sugar solution in degree per decimeter per unit concentration\n",
+"l = 2.5 // length of Polari meter in decimeter\n",
+"// Sample Problem 20 on page no. 3.29\n",
+"printf('\n # PROBLEM 20 # \n')\n",
+"c = theta / (s * l) // calculation for concentration of sugar solution\n",
+"printf('\n Standard formula used \n c = theta / (s * l). \n')\n",
+"printf('\n Concentration of sugar solution = %f gm/cc',c)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.21: Calculation_of_Specific_rotation_of_sugar_solution.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"theta = 26.4 // rotation of plane of polarization in degree\n",
+"c = 0.2 // concentration of sugar solution in gm/cc\n",
+"l = 2 // length of polarizing tube in decimeter\n",
+"// Sample Problem 21 on page no. 3.29\n",
+"printf('\n # PROBLEM 21 # \n')\n",
+"s = theta / (l * c)// calculation for specific rotation of sugar solution\n",
+"printf('Standard formula used \n s = (10*theta)/(l*c)\n')\n",
+"printf('\n Specific rotation of sugar solution = %f degree/(dm-cc)',s)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.22: Calculation_of_Specific_rotation_of_sugar_solution.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"theta = 6.5 // rotation of plane of polarization in degree\n",
+"c = 0.05 // concentration of sugar solution in gm/cc\n",
+"l = 2 // length of polarizing tube in decimeter\n",
+"// Sample Problem 22 on page no. 3.29\n",
+"printf('\n # PROBLEM 22 # \n')\n",
+"s = theta / (l * c) // calculation for specific rotation of sugar solution\n",
+"printf('\n Standard formula used \n s = theta / (l * c). \n ')\n",
+"printf('\n Specific rotation of sugar solution = %f degree/(dm-cc)',s)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.23: Calculation_of_Concentration_of_sugar_solution.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"w = 80 // weight of impure sugar in gm\n",
+"theta = 9.9 // rotation of plane of polarization in degree\n",
+"s = 66 // specific rotation of sugar solution in degree per decimeter per unit concentration\n",
+"l = 2 // length of Polari meter in decimeter\n",
+"// Sample Problem 23 on page no. 3.30\n",
+"printf('\n # PROBLEM 23 # \n')\n",
+"c = theta / (s * l) * (1000) // in gm/l\n",
+"per_c = (c * 100) / w // calculation for concentration of sugar solution\n",
+"printf('\n Standard formula used \n c = theta / (s * l) * (1000). \n per_c = (c * 100) / w. \n')\n",
+"printf('\n Concentration of sugar solution = %f percent',per_c)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.24: Calculation_of_Concentration_of_sugar_solution.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"theta = 11 // rotation of plane of polarization in degree\n",
+"s = 66 // specific rotation of sugar solution in degree per decimeter per unit concentration\n",
+"l = 2 // length of Polari meter in decimeter\n",
+"// Sample Problem 24 on page no. 3.29\n",
+"printf('\n # PROBLEM 24 # \n')\n",
+"c = theta / (s * l) // calculation for concentration of sugar solution\n",
+"printf('\n Standard formula used \n c = theta / (s * l). \n ')\n",
+"printf('\n Concentration of sugar solution = %f gm/cc',c)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.25: Calculation_of_Specific_rotation_of_sugar_solution.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"theta = 26.4 // rotation of plane of polarization in degree\n",
+"c = 0.2 // concentration of sugar solution in gm/cc\n",
+"l = 2 // length of polarizing tube in decimeter\n",
+"// Sample Problem 25 on page no. 3.30\n",
+"printf('\n # PROBLEM 25 # \n')\n",
+"s = theta / (l * c) // calculation for specific rotation of sugar solution\n",
+"printf('\n Standard formula used \n s = theta / (l * c). \n')\n",
+"printf('\n Specific rotation of sugar solution = %f degree/(dm-cc)',s)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.26: Calculation_of_Optical_rotation_of_diluted_solution.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"theta = 13 // rotation of plane of polarization in degree\n",
+"r = (1 / 3) // ratio of the final concentration to the initial solution\n",
+"l = 2 // length of Polari meter in decimeter\n",
+"l_ = 3 // length of second polarizing tube in decimeter \n",
+"// Sample Problem 26 on page no. 3.30\n",
+"printf('\n # PROBLEM 26 # \n')\n",
+"theta_ = (l_ * r * theta) / l// calculation for optical rotation of diluted solution\n",
+"printf('Standard formula used \n s=theta/(l*c)\n')\n",
+"printf('\nOptical rotation of diluted solution = %f degree',theta_)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.2: Calculation_of_Angle_of_Brewster.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"mu = 1.33 // refractive index of glass\n",
+"// Sample Problem 2 on page no. 3.24\n",
+"printf('\n # PROBLEM 2 # \n')\n",
+"Ip = atan(mu) * (180 / %pi) // by Brewster's law\n",
+"printf('Standard formula used \n mu=tan(Ip)\n')\n",
+"printf('\n Angle of brewster = %f degree',Ip)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.3: Calculation_of_difference_between_polarization_angle.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"mu_w = 1.33 // refractive index of water\n",
+"mu_g = 1.54 // refractive index of glass\n",
+"// Sample Problem 3 on page no. 3.24\n",
+"printf('\n # PROBLEM 3 # \n')\n",
+"Ip_1 = atan(mu_g / mu_w) * (180 / %pi)//calculation for polarizing angle for water\n",
+"Ip_2 = atan(mu_w / mu_g) * (180 / %pi) // calculation for polarizing angle for glass\n",
+"printf('Standard formula used \n mu=tan(Ip)\n')\n",
+"printf('\n Polarizing angle for water to glass = %f degree,\n Polarizing angle for glass to water = %f degree',Ip_1,Ip_2)\n",
+"printf('\n So polarizing angle is greater for a beam incident from water to glass')"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.4: Calculation_of_Angle_of_minimum_deviation.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"Ip = %pi / 3 // polarizing angle of piece of glass for green light in radian\n",
+"a = %pi / 3 // angle of prism in radian \n",
+"// Sample Problem 4 on page no. 3.24\n",
+"printf('\n # PROBLEM 4 # \n')\n",
+"mu = tan(Ip) // calculation for refractive index\n",
+"delta_m = 2 * (asin(mu * sin(a / 2)) - (a / 2)) * (180 / %pi) // calculation for angle of minimum deviation\n",
+"printf('\n Standard formula used \n mu = tan(Ip). \n delta_m = 2 * (asin(mu * sin(a / 2)) - (a / 2)) * (180 / pi). \n')\n",
+"printf('\n Angle of minimum deviation = %f degree',delta_m)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.5: Calculation_of_Brewster_angle.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"mu_w = 1.33 // refractive index of water\n",
+"mu_g = 1.5 // refractive index of glass\n",
+"// Sample Problem 5 on page no. 3.25\n",
+"printf('\n # PROBLEM 5 # \n')\n",
+"Ip = atan(mu_g / mu_w) * (180 / %pi) // calculation for Brewster angle\n",
+"printf('\n Standard formula used \n Ip = atan(mu_g / mu_w) * (180 / pi). \n')\n",
+"printf('\n Brewster angle = %f degree',Ip)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.6: Calculation_of_Angle_of_incidence_and_angle_of_refraction.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"mu = 1.732 // refractive index of glass\n",
+"// Sample Problem 6 on page no. 3.25\n",
+"printf('\n # PROBLEM 6 # \n')\n",
+"Ip = atan(mu) * (180 / %pi) // by Brewster's law\n",
+"r = 90 - Ip// calculation for angle of refraction\n",
+"printf('Standard formula used \n mu=tan(Ip)\n')\n",
+"printf('\n Angle of incidence = %f degree\n Angle of refraction = %f degree',Ip,r)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.7: Calculation_of_Ratio_between_transmitted_intensity_to_incident_intensity.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"alpha = %pi / 3 // angle between polarizer and analyzer\n",
+"// Sample Problem 7 on page no. 3.25\n",
+"printf('\n # PROBLEM 7 # \n')\n",
+"r = (cos(alpha))^2 // where r = transmitted intensity / incident intensity\n",
+"printf('\n Standard formula used \n r = (cos(alpha))^2. \n')\n",
+"printf('\n Ratio between transmitted intensity to incident intensity = %f ',r)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.8: Calculation_of_The_angle_between_characteristics_directions_of_the_sheet.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"r1 = 1/3 // ratio of intensity of transmitted light to the intensity of transmitted beam in first case\n",
+"r2 = 1/3 // ratio of intensity of transmitted light to the intensity of incident beam in second case\n",
+"p = 50 // percentage reduction in intensity of unpolarized light by the sheet \n",
+"// Sample Problem 8 on page no. 3.25\n",
+"printf('\n # PROBLEM 8 # \n')\n",
+"theta1 = acosd(sqrt(r1)) // calculation for the angle between characteristics directions of the sheet in first case\n",
+"theta2 = acosd(sqrt(2*r2)) // calculation for the angle between characteristics directions of the sheet in second case\n",
+"printf('\n Standard formula used \n theta = acosd(sqrt(r)). \n')\n",
+"printf('\n The angle between characteristics directions of the sheet in first case = %f degree. \n the angle between characteristics directions of the sheet in second case = %f degree.',theta1,theta2)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 3.9: Calculation_of_Angle_between_the_nicol_prisms.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"r = 3 / 4 // ratio of intensity of transmitted light to the intensity of incident light\n",
+"// Sample Problem 9 on page no. 3.26\n",
+"printf('\n # PROBLEM 9 # \n')\n",
+"theta = acos(sqrt(r)) * (180 / %pi) // calculation for angle between the nicol prisms\n",
+"printf('\n Standard formula used \n theta = acos(sqrt(r)) * (180 / pi). \n') \n",
+"printf('\n Angle between the nicol prisms = %f degree',theta)"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Engineering_Physics_by_H_K_Malik/4-LASERS_AND_HOLOGRAPHY.ipynb b/Engineering_Physics_by_H_K_Malik/4-LASERS_AND_HOLOGRAPHY.ipynb
new file mode 100644
index 0000000..048331e
--- /dev/null
+++ b/Engineering_Physics_by_H_K_Malik/4-LASERS_AND_HOLOGRAPHY.ipynb
@@ -0,0 +1,253 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 4: LASERS AND HOLOGRAPHY"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 4.1: EX4_1.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 5.5e-7 // wavelength of light in meter\n",
+"c = 3e+8 // speed of light in m/sec\n",
+"h = 6.63e-34 // Planck constant in j/sec\n",
+"e = 1.6e-19 // charge on electron in coulomb \n",
+"k = 8.62e-5 // Boltzmann constant in eV/K\n",
+"T = 300 // temperature in kelvin\n",
+"// Sample Problem 1 on page no. 4.24\n",
+"printf('\n # PROBLEM 1 # \n')\n",
+"delta_E = (h * c) / (lambda * e) // calculation for energy difference \n",
+"r = exp(-delta_E / (k * T)) // calculation for ratio of population of upper level to the lower energy level\n",
+"T_ = (delta_E / (k * 0.693)) // calculation for temperature for the second condition\n",
+"printf('\n Standard formula used \n delta_E = (h * c) / (lambda * e). \n r = exp(-delta_E / (k * T)). \n T_ = (delta_E / (k * 0.693)). \n')\n",
+"printf('\n Ratio of population of upper level to the lower energy level = %e. \n Temperature for the second condition = %f K. ',r,T_)\n",
+"//Answer in the book: 1.3 X 10^-38 and 37800 K\n",
+"//Answer in the program:1.100524 X 10^-38 and 37836.557301 K'"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 4.2: Calculation_of_Beam_divergence_angle.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda1 = 6.328e-7 // wavelength of light in first case in meter\n",
+"lambda2 =2e-7 // wavelength of light in second case in meter\n",
+"r1 = 2.3e-4 // the radius of internal beam of laser in first case in meter\n",
+"r2 = 2.4e-3 // the radius of internal beam of laser in second case in meter\n",
+"// Sample Problem 2 on page no. 4.24\n",
+"printf('\n # PROBLEM 2 # \n')\n",
+"theta1 = lambda1 / (%pi * r1) // calculation for beam divergence angle in first case\n",
+"theta2 = lambda2 / (%pi * r2) // calculation for beam divergence angle in second case\n",
+"printf('\n Standard formula used \n theta = lambda / (pi * r). \n')\n",
+"printf('\n Beam divergence angle in first case = %e radian. \n Beam divergence angle in second case = %e radian. ',theta1,theta2)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 4.3: Calculation_of_Total_energy.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"l = 6e-2 // length of laser in meter\n",
+"D = 1e-2 // diameter of laser in meter\n",
+"lambda = 6.944e-7 // wavelength of light in meter\n",
+"d = 3700 // density of aluminium oxide in kg/meter cube\n",
+"Na = 6e+23 // Avogadro number\n",
+"M = 0.102 // molar mass of aluminium oxide in kg/meter cube\n",
+"h = 4.1e-15 // Planck constant in eV-sec\n",
+"c = 3e+8 // speed of light in meter/sec\n",
+"// Sample Problem 3 on page no. 4.25\n",
+"printf('\n # PROBLEM 3 # \n')\n",
+"v = (%pi * (D^2) * l) / 4 // calculation for volume \n",
+"N = (2 * Na * d * v) / M // calculation for no. of aluminium ions\n",
+"N_ = N / 3500 // calculation for the no. of chromium ions\n",
+"E = (h * c) / lambda // calculation for the energy of stimulated emission photon \n",
+"Et = N_ * E * (1.6e-19) // calculation for total energy\n",
+"printf('\n Standard formula used \n v = (pi * (D^2) * l) / 4. \n N = (2 * Na * d * v) / M. \n N_ = N / 3500. \n E = (h * c) / lambda. \n Et = N_ * E * (1.6e-19). \n')\n",
+"printf('\n Total energy = %f J',ceil(Et))"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 4.4: Calculation_of_Power_per_unit_area_delivered_by_the_laser.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"p = 4e-3 // energy of laser pulse in meter\n",
+"r = 1.5e-5 // radius of spot in meter\n",
+"t = 1e-9 // pulse length in time in sec\n",
+"// Sample Problem 4 on page no. 4.26\n",
+"printf('\n # PROBLEM 4 # \n')\n",
+"p_ = p / t// calculation for  power in watt\n",
+"I = p_ / (%pi * r^2)// calculation for power per unit area delivered by the laser\n",
+"printf('Standard formula used \n I=P/a\n')\n",
+"printf('\nPower per unit area delivered by the laser = %e watt/square meter',I)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 4.5: Calculation_of_Power_per_unit_area_delivered_by_the_laser.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"D = 5e-3 // diameter of laser in meter\n",
+"lambda = 7.2e-7 // wavelength of light in meter\n",
+"d = 4e8 // distance at moon from earth in meter\n",
+"// Sample Problem 5 on page no. 4.26\n",
+"printf('\n # PROBLEM 5 # \n')\n",
+"r = (D / 2) // calculation for radius\n",
+"theta = (0.637 * lambda) / r // calculation for angular spread\n",
+"areal_spread = (d * theta)^2 // calculation for areal spread\n",
+"printf('\n Standard formula used \n theta = (0.637 * lambda) / r. \n areal_spread = (d * theta)^2. \n ')\n",
+"printf('\n Angular spread = %e radian ,\n Areal spread = %e square meter',theta,areal_spread)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 4.6: Calculation_of_Areal_spread_and_Intensity.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"D = 5e-3 // diameter of laser in meter\n",
+"lambda = 6.943e-7 // wavelength of light in meter\n",
+"f =0.1 // focal length in meter\n",
+"P = 0.1 // power of laser in watt\n",
+"// Sample Problem 6 on page no. 4.27\n",
+"printf('\n # PROBLEM 6 # \n')\n",
+"r = (D / 2)// calculation for \n",
+"theta = (0.637 * lambda) / r// calculation for angular spread\n",
+"areal_spread = (f * theta)^2// calculation for areal spread\n",
+"I = P / areal_spread// calculation for intensity\n",
+"printf('Standard formula used \n theta=0.637*lambda/r,\n areal spread = (theta*D)^2,\n I=P/A\n')\n",
+"printf('\n Areal spread = %e square meter,\n Intensity = %e watt/square meter',areal_spread,I)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 4.7: Calculation_of_Degree_of_non_monochromaticity.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"tou = 1e-10 // coherence time in sec\n",
+"lambda = 5.4e-7 // wavelength of light in meter\n",
+"// Sample Problem 7 on page no. 4.28\n",
+"printf('\n # PROBLEM 7 # \n')\n",
+"delta_v = 1 / tou \n",
+"v_ = (3e+8) / lambda // calculation for frequency\n",
+"d = delta_v / v_ // calculation for degree of non-monochromaticity\n",
+"printf('\n Standard formula used \n delta_v = 1 / tou. \n v_ = (3e+8) / lambda. \n d = delta_v / v_. \n ')\n",
+"printf('\n Degree of non-monochromaticity = %f ',d)"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Engineering_Physics_by_H_K_Malik/5-FIBRE_OPTICS.ipynb b/Engineering_Physics_by_H_K_Malik/5-FIBRE_OPTICS.ipynb
new file mode 100644
index 0000000..4038cd7
--- /dev/null
+++ b/Engineering_Physics_by_H_K_Malik/5-FIBRE_OPTICS.ipynb
@@ -0,0 +1,412 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 5: FIBRE OPTICS"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 5.10: Calculation_of_Number_of_modes.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"mu1 = 3.6 // refractive index for core\n",
+"mu2 = 3.55 // refractive index for cladding\n",
+"// Sample Problem 10 on page no. 5.19\n",
+"printf('\n # PROBLEM 10 # \n')\n",
+"NA = sqrt(mu1^2 - mu2^2)//calculation for numerical aperture\n",
+"Mm1 = 0.5 * (%pi * 5 * NA)^2//calculation for no. of modes in first case\n",
+"Mm2 = 0.5 * (%pi * 50 * NA)^2//calculation for no. of modes in second case\n",
+"printf('\n Standard formula used \n Mm=1/2(pi*d*NA/lambda)^2. NA=sqrt(mu1^2-mu2^2). \n')\n",
+"printf('\n Number of modes in first case = %d. \n Number of modes in second case = %d.',Mm1,Mm2)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 5.11: Calculation_of_Maximum_diameter_of_core.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 1.25e-6 //wavelength of light in meter\n",
+"mu1 = 1.46 // refractive index for core\n",
+"mu2 = 1.457 // refractive index for cladding\n",
+"// Sample Problem 11 on page no. 5.20\n",
+"printf('\n # PROBLEM 11 # \n')\n",
+"NA = sqrt(mu1^2 - mu2^2)//calculation for numerical aperture\n",
+"k = (2.4 * lambda) / ( %pi * NA)\n",
+"printf('\n Standard formula used \n d<8*lambda/(pi*NA)\n')\n",
+"printf('\n Maximum diameter of core = %f micro meter',k*1e6)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 5.12: Calculation_of_Absorption_coefficient.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"L = 0.1 // length of fiber in km\n",
+"p = 5e-6 // power of signal in watt\n",
+"p_ = 1e-6 // power of signal inside the fiber in watt\n",
+"// Sample Problem 12 on page no. 5.20\n",
+"printf('\n # PROBLEM 12 # \n')\n",
+"alpha = (10 * log10(p / p_)) / L//calculation for absorption coefficient\n",
+"printf('\n Standard formula used \n alpha=10/L*log(Pi/Po).\n')\n",
+"printf('\n Absorption coefficient = %f dB/km. ',alpha)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 5.13: Calculation_of_Output_power.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"L = 3 // length of optical fiber in km\n",
+"l = 6 // losses in dB\n",
+"p = 5e-3 // input power in watt \n",
+"// Sample Problem 13 on page no. 5.20\n",
+"printf('\n # PROBLEM 13 # \n')\n",
+"alpha = (l * 3) / L\n",
+"p_ = p / (exp((2.303 * alpha * L) / 10))\n",
+"printf('\n Standard formula used \n alpha = (l * 3) / L. \n p_ = p / (exp((2.303 * alpha * L) / 10)). \n')\n",
+"printf('\n Output power = %f mW. ',p_*1e3)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 5.1: Calculation_of_Critical_angle_and_Numerical_aperture_and_Maximum_incidence_angle.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"mu1 = 1.52 // refractive index for core\n",
+"mu2 = 1.41 // refractive index for cladding\n",
+"// Sample Problem 1 on page no. 5.15\n",
+"printf('\n # PROBLEM 1 # \n')\n",
+"theta_c = asin(mu2 / mu1) * (180 / %pi)\n",
+"NA = sqrt(mu1^2 - mu2^2)\n",
+"theta_0 = asin(NA) * (180 / %pi)\n",
+"printf('\n Standard formula used \n theta_c = asin(mu2 / mu1) * (180 / pi). \n NA = sqrt(mu1^2 - mu2^2). \n theta_0 = asin(NA) * (180 / pi). \n')\n",
+"printf('\n Critical angle = %f degree. \n Numerical aperture = %f,\n Maximum incidence angle = %f degree.',theta_c,NA,theta_0)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 5.2: Calculation_of_Numerical_aperture_and_Maximum_incidence_angle.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"mu1 = 1.6 // refractive index for core\n",
+"mu2 = 1.5 // refractive index for cladding\n",
+"// Sample Problem 2 on page no. 5.16\n",
+"printf('\n # PROBLEM 2 # \n')\n",
+"NA = sqrt(mu1^2 - mu2^2)//calculation for numerical aperture\n",
+"theta_0 = asin(NA) * (180 / %pi)//calculation for maximum incidence angle\n",
+"printf('Standard formula used \n NA=aqrt(mu1^2-mu2^2),\n sin(theta_)=NA. \n')\n",
+"printf('\n Numerical aperture = %f.\n Maximum incidence angle = %f degree.',NA,theta_0)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 5.3: EX5_3.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"mu_0 = 1 // refractive index of air\n",
+"mu1 = 1.5 // refractive index for core\n",
+"mu2 = 1.48 // refractive index for cladding\n",
+"// Sample Problem 3 on page no. 5.16\n",
+"printf('\n # PROBLEM 3 # \n')\n",
+"theta_c = asin(mu2 / mu1) * (180 / %pi)\n",
+"delta_mu = (mu1 - mu2) / mu1\n",
+"NA = sqrt(mu1^2 - mu2^2)\n",
+"theta_0 = asin(NA) * (180 / %pi)\n",
+"printf('\n Standard formula used \n theta_c = asin(mu2 / mu1) * (180 / pi). \n delta_mu = (mu1 - mu2) / mu1. \n NA = sqrt(mu1^2 - mu2^2). \n theta_0 = asin(NA) * (180 / pi). \n ')\n",
+"printf('\n Critical angle = %f degree. \n Numerical aperture = %f. \n Acceptance angle = %f degree.\n Fractional refractive index = %f.',theta_c,NA,theta_0,delta_mu)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 5.4: Calculation_of_Numerical_aperture_and_Maximum_incidence_angle.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"mu1 = 1.62 // refractive index for core\n",
+"mu2 = 1.52 // refractive index for cladding\n",
+"// Sample Problem 4 on page no. 5.17\n",
+"printf('\n # PROBLEM 4 # \n')\n",
+"NA = sqrt(mu1^2 - mu2^2)\n",
+"theta_0 = asin(NA) * (180 / %pi)\n",
+"printf('\n Standard formula used \n NA = sqrt(mu1^2 - mu2^2). \n theta_0 = asin(NA) * (180 / pi). \n')\n",
+"printf('\n Numerical aperture = %f. \n Maximum incidence angle = %f degree.',NA,theta_0)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 5.5: Calculation_of_Refractive_index_for_core_Refractive_index_for_cladding.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"NA = 0.22 // numerical aperture\n",
+"delta_mu = 0.012 // fractional refractive index\n",
+"// Sample Problem 5 on page no. 5.17\n",
+"printf('\n # PROBLEM 5 # \n')\n",
+"mu1 = sqrt(NA^2 / (1 - (1 - delta_mu)^2))\n",
+"mu2 = (1 - delta_mu) * mu1\n",
+"printf('\n Standard formula used \n mu1 = sqrt(NA^2 / (1 - (1 - delta_mu)^2)). \n mu2 = (1 - delta_mu) * mu1. \n')\n",
+"printf('\n Refractive index for core = %f.\n Refractive index for cladding = %f.',mu1,mu2)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 5.6: EX5_6.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"d = 0.0064 // diameter of fiber in cm\n",
+"mu1 = 1.53 // refractive index for core\n",
+"mu2 = 1.39 // refractive index for clad\n",
+"L = 90 // length of fiber in cm\n",
+"mu_0 = 1 // refractive index of air\n",
+"// Sample Problem 6 on page no. 5.17\n",
+"printf('\n # PROBLEM 6 # \n')\n",
+"NA = sqrt(mu1^2 - mu2^2)\n",
+"theta_0 = asin(NA) * (180 / %pi)\n",
+"N1 = L / (d * sqrt((mu1 / (mu_0 * sin(theta_0 * (%pi / 180))))^2 - 1))\n",
+"N2 = L / (d * sqrt((mu1 / (mu_0 * sin(theta_0 * (%pi / 360))))^2 - 1))\n",
+"printf('\n Standard formula used \n NA = sqrt(mu1^2 - mu2^2). \n theta_0 = asin(NA) * (180 / pi). \n N = L / (d * sqrt((mu / (mu_0 * sin(theta_0 * (pi / 180))))^2 - 1)). \n ')\n",
+"printf('\n Numerical aperture = %f.\n Acceptance angle = %f degree. \n Number of reflections at maximum incidence = %f. \n Number of reflections in second case = %f. ',NA,theta_0,N1,N2)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 5.7: Calculation_of_The_normalized_frequency_and_number_of_guided_in_the_core.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"d = 0.05 // diameter of fiber in mm\n",
+"NA = 0.22 // numerical aperture\n",
+"lambda = 8.5e-4 // wavelength of light in mm\n",
+"// Sample Problem 7 on page no. 5.18\n",
+"printf('\n # PROBLEM 7 # \n')\n",
+"Vn = (%pi * d * NA) / lambda\n",
+"Mm = 0.5 * (Vn)^2\n",
+"printf('\n Standard formula used \n Vn = (pi * d * NA) / lambda. \n Mm = 0.5 * (Vn)^2. \n')\n",
+"printf('\n The normalized frequency = %f,\n number of guided in the core = %f',Vn,Mm)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 5.8: Calculation_of_Diameter_of_core_and_number_of_modes.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 1.25e-6 //wavelength of light in meter\n",
+"mu1 = 1.465 // refractive index for core\n",
+"mu2 = 1.460 // refractive index for cladding\n",
+"// Sample Problem 8 on page no. 5.18\n",
+"printf('\n # PROBLEM 8 # \n')\n",
+"NA = sqrt(mu1^2 - mu2^2)\n",
+"k = (2.4 * lambda) / ( %pi * NA)\n",
+"Mm = 0.5 * ((%pi * 50e-6 * NA) / lambda)^2\n",
+"printf('\n Standard formula used \n NA = sqrt(mu1^2 - mu2^2). \n k = (2.4 * lambda) / ( pi * NA). \n Mm = 0.5 * ((pi * 50e-6 * NA) / lambda)^2. \n ')\n",
+"printf('\n Diameter of core < %e meter,\n number of modes = %d',k,Mm)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 5.9: Calculation_of_Numerical_aperture_and_Number_of_modes.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"lambda = 0.85e-6 //wavelength of light in meter\n",
+"mu1 = 1.461 // refractive index for core\n",
+"mu2 = 1.456 // refractive index for clad\n",
+"d = 4e-5 // diameter of core in meter\n",
+"// Sample Problem 9 on page no. 5.19\n",
+"printf('\n # PROBLEM 9 # \n')\n",
+"NA = sqrt(mu1^2 - mu2^2)\n",
+"Mm = 0.5 * ((%pi * d * NA) / lambda)^2\n",
+"printf('\n Standard formula used \n NA = sqrt(mu1^2 - mu2^2). \n Mm = 0.5 * ((pi * d * NA) / lambda)^2. \n ')\n",
+"printf('\n Numerical aperture = %f.\n Number of modes = %d. ',NA,Mm)"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Engineering_Physics_by_H_K_Malik/6-ELECTRON_OPTICS.ipynb b/Engineering_Physics_by_H_K_Malik/6-ELECTRON_OPTICS.ipynb
new file mode 100644
index 0000000..09599bf
--- /dev/null
+++ b/Engineering_Physics_by_H_K_Malik/6-ELECTRON_OPTICS.ipynb
@@ -0,0 +1,318 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 6: ELECTRON OPTICS"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.10: Calculation_of_Internal_electric_field.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"v = 1e6 // velocity of ion beam in m/sec\n",
+"B = 1 // magnetic field in tesla\n",
+"// Sample Problem 10 on page no. 6.24\n",
+"printf('\n # PROBLEM 10 # \n')\n",
+"E = B * v\n",
+"printf('\n Standard formula used \n E = B * v. \n')\n",
+"printf('\n Internal electric field = %e V/m',E)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.12: Calculation_of_Ratio_of_the_new_focus_length_to_the_initial_focus_length.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"r = 1.1 // ratio of new number of turns to the initial number of turns\n",
+"// Sample Problem 12 on page no. 6.24\n",
+"printf('\n # PROBLEM 12 # \n')\n",
+"r_ = (1 / r)^2\n",
+"printf('\n Standard formula used \n r_ = (1 / r)^2. \n')\n",
+"printf('\n Ratio of the new focus length to the initial focus length = %f ',r_)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.1: EX6_1.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"V = 500 // voltage across the electrode in eV\n",
+"m = 9e-31 // mass of electron in kg\n",
+"e = 1.6e-19 // charge on an electron in coulomb\n",
+"// Sample Problem 1 on page no. 6.20\n",
+"printf('\n # PROBLEM 1 # \n')\n",
+"E = e * V\n",
+"v = sqrt((2 * e * V) / m)\n",
+"p = m * v\n",
+"printf('\n Standard formula used \n E = e * V. \n v = sqrt((2 * e * V) / m). \n p = m * v. \n ')\n",
+"printf('\n Energy gained by electron = %e J,\n Speed of electron = %e meter/sec,\n Momentum of electron = %e kg-meter/sec',E,v,p)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.2: Calculation_of_Momentum_of_acceleration.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"v = 2.5e6 // speed of electron in meter/sec\n",
+"B = 2e-4 // magnetic field in tesla\n",
+"r = 1.76e11 // ratio of charge on electron to the mass of electron in C/kg\n",
+"// Sample Problem 2 on page no. 6.20\n",
+"printf('\n # PROBLEM 2 # \n')\n",
+"a = (B * r * v)\n",
+"printf('\n Standard formula used \n a = (B * r * v). \n ')\n",
+"printf('\n Momentum of acceleration = %e meter/square sec.',a)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.4: Calculation_of_Radius_of_circle_traced_by_the_beam_and_Speed_of_beam.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"v = 5.2e6 // speed of electron in meter/sec\n",
+"B = 1.3e-4 // magnetic field in tesla\n",
+"r = 1.76e11 // ratio of charge on electron to the mass of electron in C/kg\n",
+"E = 3.2e-12 // energy of the electron beam in J\n",
+"M = 9e-31 // mass of an electron in kg\n",
+"// Sample Problem 4 on page no. 6.22\n",
+"printf('\n # PROBLEM 4 # \n')\n",
+"R = v / (r * B)\n",
+"v_ = sqrt((2 * E) / M )\n",
+"printf('\n Standard formula used \n R = v / (r * B). \n v_ = sqrt((2 * E) / M ). \n')\n",
+"printf('\n Radius of circle traced by the beam = %f cm. \n Speed of beam in second case = %e meter/sec.\n Speed of beam in second case is greater than speed of light so we cannot use above formula.',R*100,v_)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.5: Calculation_of_Ratio_of_the_charge_on_an_electron_to_the_mass_of_an_electron.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"V = 2.500e3 // voltage across the electrode in V\n",
+"E = 3.6e4 // strength of electric field in V/m\n",
+"B = 1.2e-3 // magnetic field in tesla\n",
+"// Sample Problem 5 on page no. 6.22\n",
+"printf('\n # PROBLEM 5 # \n')\n",
+"r = (E / B)^2 / (2 * V)//calculation for ratio of the charge on an electron to the mass of an electron\n",
+"printf('\n Standard formula used \n e/m=(E/B)^2 / (2V). \n')\n",
+"printf('\n Ratio of the charge on an electron to the mass of an electron = %e C/kg.',r)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.6: Calculation_of_Lamoure_radius.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"M = 9.1e-31 // mass of electron in kg\n",
+"E = 1.6e-15 // energy of electron in J\n",
+"B = 5e-5 // magnetic field in tesla\n",
+"e = 1.6e-19 // charge on an electron in coulomb\n",
+"// Sample Problem 6 on page no. 6.23\n",
+"printf('\n # PROBLEM 6 # \n')\n",
+"v = sqrt((2 * E) / M)\n",
+"r = (M * v) / (e * B)\n",
+"printf('\n Standard formula used \n v = sqrt((2 * E) / M). \n r = (M * v) / (e * B). \n')\n",
+"printf('\n Larmoure radius = %f meter',r)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.7: Calculation_of_Lamoure_radius.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"Mp = 1.67e-27 // mass of proton in kg\n",
+"v = 3e5 // speed of proton in meter/sec\n",
+"B = 5e-9 // magnetic field in tesla\n",
+"e = 1.6e-19 // charge on a proton in coulomb\n",
+"// Sample Problem 7 on page no. 6.23\n",
+"printf('\n # PROBLEM 7 # \n')\n",
+"r = (Mp * v) / (e * B)//calculation for Larmour radius\n",
+"printf('\n Standard formula used \n r=m*v/(e*B). \n')\n",
+"printf('\n Larmour radius = %e meter',r)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.8: Calculation_of_Area_traced_by_the_trajectory_of_helium_ion.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"M = 6.68e-27 // mass of helium ion in kg\n",
+"E = 1.6e-16 // energy of helium ion in J\n",
+"B = 5e-2 // magnetic field in tesla\n",
+"e = 1.6e-19 // charge on helium ion in coulomb\n",
+"// Sample Problem 8 on page no. 6.23\n",
+"printf('\n # PROBLEM 8 # \n')\n",
+"v = sqrt((2 * E) / M)//calculation for velocity\n",
+"r = (M * v) / (e * B)//calculation for Larmour radius\n",
+"A = %pi * r^2//calculation for area traced by the trajectory of helium ion\n",
+"printf('Standard formula used \n E=1/2*m*v^2,\n Rl=m*v/(e*B),\n A=pi*r^2\n')\n",
+"printf('\n Area traced by the trajectory of helium ion = %f square meter',A)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 6.9: Calculation_of_The_drift_of_the_guiding_center.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"E = 100 // strength of electric field in V/m\n",
+"B = 1e-3 // magnetic field in tesla\n",
+"// Sample Problem 9 on page no. 6.24\n",
+"printf('\n # PROBLEM 9 # \n')\n",
+"v = E / B\n",
+"printf('\n Standard formula used \n v = E / B. ')\n",
+"printf('\n The drift of the guiding center = %e m/sec',v)"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Engineering_Physics_by_H_K_Malik/7-WAVES_AND_OSCILLATIONS.ipynb b/Engineering_Physics_by_H_K_Malik/7-WAVES_AND_OSCILLATIONS.ipynb
new file mode 100644
index 0000000..93ae534
--- /dev/null
+++ b/Engineering_Physics_by_H_K_Malik/7-WAVES_AND_OSCILLATIONS.ipynb
@@ -0,0 +1,431 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 7: WAVES AND OSCILLATIONS"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 7.10: Calculation_of_Time_period_of_pendulum.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"f = 3 // acceleration of pendulum in m/sec^2\n",
+"l = 1 // length of pendulum in meter\n",
+"g = 9.8 // acceleration due to gravity in m/sec^2\n",
+"// Sample Problem 10 on page no. 7.25\n",
+"printf('\n # PROBLEM 10 # \n')\n",
+"T = 2 * %pi * sqrt(l / (g + f))\n",
+"printf('\n Standard formula used \n T = 2 * pi * sqrt(l / (g + f)). \n ') \n",
+"printf('\n Time period of pendulum = %f sec.',T)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 7.11: Calculation_of_Time_period_of_motion.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"x = 0.3 // stretch in spring in meter\n",
+"m1 = 6 // mass of first body in kg\n",
+"m2 = 1 // mass of second body in kg\n",
+"g = 9.8 //  gravitational acceleration of earth in m/sec^2\n",
+"// Sample Problem 11 on page no. 7.26\n",
+"printf('\n # PROBLEM 11 # \n')\n",
+"k = (m1 * g) / x\n",
+"T = (2 * %pi) * sqrt(m2 / k)\n",
+"printf('\n Standard formula used \n k = (m1 * g) / x. \n T = (2 * pi) * sqrt(m2 / k).\n')\n",
+"printf('\n Time period of motion = %f sec. ',T)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 7.12: EX7_12.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"x = 0.1 // compression in spring in m\n",
+"F = 10 // restoring force in N\n",
+"m = 4 // mass of body in kg\n",
+"g = 9.8 // acceleration due to gravity in m/sec^2\n",
+"// Sample Problem 12 on page no. 7.26\n",
+"printf('\n # PROBLEM 12 # \n')\n",
+"k = F / x\n",
+"F_ = m * g\n",
+"x_ = F_ / k\n",
+"T = (2 * %pi) * sqrt(m / k)\n",
+"printf('\n Standard formula used \n k = F / x. \n F_ = m * g. \n x_ = F_ / k. \n T = (2 * pi) * sqrt(m / k). \n ')\n",
+"printf('\n Time period of motion = %f sec. \n Compression of the spring due to the weight of the body = %f m. ',T,x_)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 7.13: Calculation_of_Time.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"t = 50 // relaxation time in sec\n",
+"r = 1 / exp(1) // falls in amplitude and energy\n",
+"// Sample Problem 13 on page no. 7.26\n",
+"printf('\n # PROBLEM 13 # \n')\n",
+"s = 1 / (2 * t)\n",
+"T = 1 / s // by using formula A=A_exp(-st) and using r=A/A_\n",
+"printf('\n Standard formula used \n s = 1 / (2 * t). \n T = 1 / s . \n ')\n",
+"printf('\n Time = %f sec',T)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 7.14: Calculation_of_Time.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"n = 260 // frequency in Hz\n",
+"Q = 2000 // quality factor\n",
+"r = 1 / (exp(1)^2) // decrease in amplitude \n",
+"// Sample Problem 14 on page no. 7.27\n",
+"printf('\n # PROBLEM 14 # \n')\n",
+"tou = Q / (2 * %pi * n)\n",
+"t = 2 * tou // by using formula A=A_exp(-st) and using r=A/A_\n",
+"printf('\n Standard formula used \n tou = Q / (2 * pi * n). \n t = 2 * tou. \n')\n",
+"printf('\n Time = %f sec.',t)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 7.1: Calculation_of_Amplitude_and_Mass_of_particle.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"E = 1.024e-3 // total energy of particle in J\n",
+"T = 2 * %pi // time period of S.H.M. in sec\n",
+"x = 0.08 * sqrt(2) // distance of partile in meter\n",
+"t = %pi / 4 // time in second\n",
+"// Sample Problem 1 on page no. 7.22\n",
+"printf('\n # PROBLEM 1 # \n')\n",
+"A = x / sin((2 * %pi * t) / T)\n",
+"M = (E * T^2) / (2 * %pi^2 * A^2)\n",
+"printf('\n Standard formula used \n A = x / sin((2 * pi * t) / T). \n M = (E * T^2) / (2 * pi^2 * A^2). \n')\n",
+"printf('\n Amplitude = %f meter,\n Mass of particle = %f g',A,M/1e-3)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 7.2: Calculation_of_Maximum_amplitude_of_velocity.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"A = 0.05 // amplitude in meter\n",
+"T = 10 // time period of S.H.M. in sec\n",
+"// Sample Problem 2 on page no. 7.22\n",
+"printf('\n # PROBLEM 2 # \n')\n",
+"v = (A * 2 * %pi) / T\n",
+"printf('\n Standard formula used \n v = (A * 2 * pi) / T')\n",
+"printf('\n Maximum amplitude of velocity = %f meter/sec',v)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 7.3: 3Calculation_of_Force_constant_and_Time_period.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"E = 9 // total energy of particle in J\n",
+"U = 5 // potential energy in J\n",
+"A = 1 // amplitude in meter\n",
+"m = 2 // mass of harmonic oscillator in kg\n",
+"// Sample Problem 3 on page no. 7.23\n",
+"printf('\n # PROBLEM 3 # \n')\n",
+"kE = E - U// calculation for kinetic energy\n",
+"k = (2 * kE) / A^2// calculation for force constant\n",
+"T = (2 * %pi) * sqrt(m / k)// calculation for time period\n",
+"printf('Standard formula used \n k.E.=1/2*k*A^2,\n T=2*pi*sqrt(m/k)\n')\n",
+"printf('\n Force constant = %f J/m,\n Time period = %f sec',k,T)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 7.4: Calculation_of_Time_taken_by_the_particle.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"A = 0.06 // amplitude in meter\n",
+"T = 6 // time period of S.H.M. in sec\n",
+"x = 0.03 // position of particle in meter\n",
+"// Sample Problem 4 on page no. 7.23\n",
+"printf('\n # PROBLEM 4 # \n')\n",
+"delta = asin(1) // by the formula x=Asin(wt+delta) and (at t = 0,x=A) \n",
+"t = x / (A * sin(((2 * %pi) / T) + delta))\n",
+"printf('\n Standard formula used \n x=Asin(wt+delta). \n ')\n",
+"printf('\n Time taken by the particle = %f sec',t)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 7.5: Calculation_of_Maximum_velocity_and_acceleration.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"A = 0.05// amplitude in meter\n",
+"T = 10 * %pi // time period of s.h.m. in sec\n",
+"// Sample Problem 5 on page no. 7.24\n",
+"printf('\n # PROBLEM 5 # \n')\n",
+"v = A * (2 * %pi / T)\n",
+"a = A * (2 * %pi / T)^2\n",
+"printf('\n Standard formula used \n v = A * (2 * pi / T). \n a = A * (2 * pi / T)^2. \n ')\n",
+"printf('\n Maximum velocity = %e meter/sec,\n acceleration = %e m/sec^2',v,a)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 7.6: Calculation_of_Maximum_velocity.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"A = 0.06// amplitude in meter\n",
+"T = 10 * %pi // time period of s.h.m. in sec\n",
+"// Sample Problem 6 on page no. 7.24\n",
+"printf('\n # PROBLEM 6 # \n')\n",
+"v = A * (2 * %pi / T)\n",
+"printf('\n Standard formula used \n v = A * (2 * pi / T)')\n",
+"printf('\n Maximum velocity = %e meter/sec',v)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 7.7: Calculation_of_natural_frequency.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"k = 16 // stiffness constant of spring n/m\n",
+"m = 1 // mass of particle in kg\n",
+"// Sample Problem 7 on page no. 7.24\n",
+"printf('\n # PROBLEM 7 # \n')\n",
+"n = sqrt(k / m) / (2 * %pi)\n",
+"printf('\n Standard formula used \n n = sqrt(k / m) / (2 * pi).\n')\n",
+"printf('\n natural frequency = %f Hz.',n)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 7.8: Calculation_of_The_time_period_of_pendulum.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"l = 1 // length of pendulum in meter\n",
+"m = 2 // mass of particle in kg\n",
+"g = 9.8 // acceleration due to gravity in m/sec^2\n",
+"// Sample Problem 8 on page no. 7.25\n",
+"printf('\n # PROBLEM 8 # \n')\n",
+"T = 2 * %pi * sqrt(l / g)\n",
+"printf('\n Standard formula used \n T = 2 * pi * sqrt(l / g). \n')\n",
+"printf('\n The time period of pendulum = %f sec.',T)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 7.9: Calculation_of_Frequency.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"m = 100 // mass of particle in gm\n",
+"// Sample Problem 9 on page no. 7.25\n",
+"printf('\n # PROBLEM 9 # \n')\n",
+"n = (1 / (2 * %pi)) * sqrt(10 / m) // by using given formula \n",
+"printf('\n Standard formula used \n n = (1 / (2 * pi)) * sqrt(10 / m). \n')\n",
+"printf('\n Frequency  = %f Hz.',n)"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Engineering_Physics_by_H_K_Malik/8-SOUND_WAVES_AND_ACOUSTICS_OF_BUILDINGS.ipynb b/Engineering_Physics_by_H_K_Malik/8-SOUND_WAVES_AND_ACOUSTICS_OF_BUILDINGS.ipynb
new file mode 100644
index 0000000..3fb963d
--- /dev/null
+++ b/Engineering_Physics_by_H_K_Malik/8-SOUND_WAVES_AND_ACOUSTICS_OF_BUILDINGS.ipynb
@@ -0,0 +1,347 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 8: SOUND WAVES AND ACOUSTICS OF BUILDINGS"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.1: Calculation_of_Wavelength_range_of_the_sound_wave.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"v = 34500 // speed of sound in cm/sec\n",
+"f = 20 // lower limit of frequency for human hearing ear in Hz\n",
+"f_ = 20000 // upper limit of frequency for human hearing ear in Hz\n",
+"// Sample Problem 1 on page no. 8.17\n",
+"printf('\n # PROBLEM 1 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' V = f*lambda \n \n' )\n",
+"lambda = v / f\n",
+"lambda_ = v / f_\n",
+"printf('\n Wavelength range of the sound wave is %f cm to %f cm.',lambda_,lambda)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.2: Calculation_of_Velocity_of_sound_in_the_air.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"T = 373 // temperature in kelvin\n",
+"d = 1.293e-3 // density of air at S.T.P. in gm/cm^3\n",
+"d_ = 13.6 // density of mercury in gm/cm^3\n",
+"s = 0.2417 // specific heat of air at constant pressure \n",
+"s_ = 0.1715 // specific heat of air at constant volume\n",
+"g = 980 // gravitational constant i dynes/cm^3\n",
+"// Sample Problem 2 on page no. 8.18\n",
+"printf('\n # PROBLEM 2 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' nu = (gamma*p/rho)^1/2  \n gamma = C_p/C_v \n p =rho*g*h \n' )\n",
+"p = 76 * d_ * g\n",
+"gama = s / s_\n",
+"v = sqrt(gama * (p / d))\n",
+"v_ = v * sqrt(T / 273)\n",
+"printf('\n Velocity of sound in the air in %f cm/sec.',v_)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.3: Calculation_of_Ratio_of_two_principal_specific_heats_of_air.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"n = 512 // frequency of tuning fork in Hz \n",
+"T = 290 // temperature in kelvin\n",
+"lambda = 66.5 // wavelength of the gas emitted by tuning fork in cm\n",
+"d = 1.293e-3 // density of air at S.T.P. in gm/cm^3\n",
+"d_ = 13.6 // density of mercury in gm/cm^3\n",
+"g = 980 // gravitational constant i dynes/cm^3\n",
+"// Sample Problem 3 on page no. 8.18\n",
+"printf('\n # PROBLEM 3 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' nu = (gamma*p/rho)^1/2  \n p =rho*g*h \n\n' )\n",
+"p = 76 * d_ * g// calculation for pressure\n",
+"v_ = n * lambda// calculation for velocity of sound in air at temperature 17 c \n",
+"v = v_ * sqrt(273 / T)// calculation for velocity of sound in air at temp 0 c\n",
+"gama = v^2 * (d / p)// calculation for ratio of two specific heat\n",
+"printf('\n Ratio of  two principal specific heats of air is %f',gama)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.4: EX8_4.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"A = 15 * 30 // area of the floor in square meter\n",
+"h = 6 // height of hall in meter\n",
+"N = 500 // no. of people\n",
+"t = 1.36 // optimum time for orchestral music in sec\n",
+"k = 0.44 // absorption coefficient per person\n",
+"// Sample Problem 4 on page no. 8.19\n",
+"printf('\n # PROBLEM 4 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' T = 0.161 V/a*S \n' )\n",
+"aS = 0.161 * ((A * h) / t)\n",
+"a = N * k\n",
+"a_ = aS - a\n",
+"w = a_ + (N / 2) * k + (N / 2) * 0.02\n",
+"t = (0.161 * (A * h)) / w\n",
+"printf('\n Coefficient of absorption to be provided by the walls, floor and ceiling when the hall is fully occupied is %f SI unit.\n Reverberation time if only half upholstered seats are occupied is %f sec.',a_,t)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.5: Calculation_of_The_total_absorption_constant.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"V = 8000 // volume of hall in meter^3\n",
+"t = 1.8 // reverberation time in sec\n",
+"// Sample Problem 5 on page no. 8.19\n",
+"printf('\n # PROBLEM 5 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' T = 0.161 V/a*S \n' )\n",
+"aS = (0.161 * V) / t// calculation for the total absorption constant\n",
+"printf('\n The total absorption constant = %f O.W.U.',aS)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.6: Calculation_of_Reverberation_time.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"V = 1700 // volume in meter^3\n",
+"a1 = 98 // area of plastered wall in m^2\n",
+"a2 = 144 // area of plastered ceiling in m^2\n",
+"a3 = 15 // area of wooden door in m^2\n",
+"a4 = 88 // area of cushioned chairs in m^2\n",
+"a5 = 150 // area of audience (each person) in m^2\n",
+"k1 = 0.03 // coefficient of absorption for plastered wall in O.W.U.\n",
+"k2 = 0.04 // coefficient of absorption for plastered ceiling in O.W.U.\n",
+"k3 = 0.06 // coefficient of absorption for wooden door in O.W.U.\n",
+"k4 = 1 // coefficient of absorption for cushioned chair in O.W.U.\n",
+"k5 = 4.7 // coefficient of absorption for audience (each person) in O.W.U.\n",
+"// Sample Problem 6 on page no. 8.20\n",
+"printf('\n # PROBLEM 6 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' T = 0.161 V/a*S \n' )\n",
+"A1 = a1 * k1// calculation for the absorption by the plaster wall\n",
+"A2 = a2 * k2// calculation for the absorption by the plastered ceiling\n",
+"A3 = a3 * k3// calculation for wooden door\n",
+"A4 = a4 * k4// calculation for cushioned chairs \n",
+"A = A1 + A2 + A3 + A4// calculation for total absorption\n",
+"T = 0.161 * (V / A)// calculation for reverberation time\n",
+"printf('\n Reverberation time is %f sec.',T)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.7: Calculation_of_Reverberation_time.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"V = 1400 // volume of hall in meter^3\n",
+"C = 110 // seating capacity of hall \n",
+"a1 = 98 // area of plastered wall in m^2\n",
+"a2 = 144 // area of plastered ceiling in m^2\n",
+"a3 = 15 // area of wooden door in m^2\n",
+"a4 = 88 // area of cushioned chairs in m^2\n",
+"a5 = 150 // area of audience (each person) in m^2\n",
+"k1 = 0.03 // coefficient of absorption for plastered wall in O.W.U.\n",
+"k2 = 0.04 // coefficient of absorption for plastered ceiling in O.W.U.\n",
+"k3 = 0.06 // coefficient of absorption for wooden door in O.W.U.\n",
+"k4 = 1 // coefficient of absorption for cushioned chair in O.W.U.\n",
+"k5 = 4.7 // coefficient of absorption for audience (each person) in O.W.U.\n",
+"// Sample Problem 7 on page no. 8.20\n",
+"printf('\n # PROBLEM 7 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' T = 0.161 V/a*S \n' )\n",
+"A1 = a1 * k1// calculation for the absorption by the plaster wall\n",
+"A2 = a2 * k2// calculation for the absorption by the plastered ceiling\n",
+"A3 = a3 * k3// calculation for wooden door\n",
+"A4 = a4 * k4// calculation for cushioned chairs \n",
+"A5 = C*k5 // the absorption due to persons\n",
+"A = A1 + A2 + A3 + A4 + A5 // calculation for total absorption\n",
+"T = (0.161 * V) / A// calculation for the reverberation time\n",
+"printf('\n Reverberation time is %f sec.',T)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.8: Calculation_of_Reverberation_time.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"V = 980 // volume in meter^3\n",
+"a1 = 150 // area of wall in m^2\n",
+"a2 = 95 // area of ceiling in m^2\n",
+"a3 = 90 // area of floor in m^2\n",
+"k1 = 0.03 // coefficient of absorption for wall in O.W.U.\n",
+"k2 = 0.80 // coefficient of absorption for ceiling in O.W.U.\n",
+"k3 = 0.06 // coefficient of absorption for floor in O.W.U.\n",
+"// Sample Problem 8 on page no. 8.21\n",
+"printf('\n # PROBLEM 8 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' T = 0.161 V/a*S \n' )\n",
+"A1 = a1 * k1\n",
+"A2 = a2 * k2\n",
+"A3 = a3 * k3\n",
+"A = A1 + A2 + A3\n",
+"T = 0.161 * (V / A)\n",
+"printf('\n Reverberation time = %f sec',T)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 8.9: Calculation_of_Acoustic_power.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"V = 980 // volume in meter^3\n",
+"a = 1.58 // area of window in m^2\n",
+"I_ = 1e-12 // standard intensity level of sound wave in W/m^2\n",
+"l = 60 // intensity level in dB\n",
+"// Sample Problem 9 on page no. 8.21\n",
+"printf('\n # PROBLEM 9 # \n')\n",
+"I = I_ * 10^(l / 10)// calculation for intensity\n",
+"AP = I * a// calculation for acoustic power\n",
+"printf('Standard formula used \n Intensity level=10log(I/I_),\nAP=I*A\n')\n",
+"printf('\n Acoustic power = %e watt.',AP)"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}
diff --git a/Engineering_Physics_by_H_K_Malik/9-DIELECTRICS.ipynb b/Engineering_Physics_by_H_K_Malik/9-DIELECTRICS.ipynb
new file mode 100644
index 0000000..8b98e21
--- /dev/null
+++ b/Engineering_Physics_by_H_K_Malik/9-DIELECTRICS.ipynb
@@ -0,0 +1,216 @@
+{
+"cells": [
+ {
+		   "cell_type": "markdown",
+	   "metadata": {},
+	   "source": [
+       "# Chapter 9: DIELECTRICS"
+	   ]
+	},
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 9.1: Calculation_of_Polarization_vector_and_Displacement_vector.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"E = 10^6 // electric field inside the plates in V/m\n",
+"d = 0.02 // distance between the plates in meter\n",
+"k = 3 // dielectric constant of slab\n",
+"e_ = 8.85e-12 // electric permittivity of air in C^2/Nm^2\n",
+"// Sample Problem 1 on page no. 9.11\n",
+"printf('\n # PROBLEM 1 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' D = e_*E+p. \n D=e_*k*E.\n\n ')\n",
+"D = e_*k*E\n",
+"P = D-e_*E\n",
+"printf('Polarization vector is %e C/m^2. \n Displacement vector is %e C/m^2',P,D)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 9.2: Calculation_of_The_included_charge_density_on_the_surface_of_the_dielectric.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"E1 = 3*10^5 // electric intensity when space between plates evacuated in V/m\n",
+"E2 = 1*10^5 // electric intensity when space between plates is filled with dielectric in V/m\n",
+"e_ = 8.85e-12 // electric permittivity of air in C^2/Nm^2\n",
+"// Sample Problem 2 on page no. 9.11\n",
+"printf('\n # PROBLEM 2 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' E = E_-P/e_.\n\n ')\n",
+"sigma = e_*(E1 - E2)\n",
+"printf('The included charge density on the surface of the dielectric is %e C/m^2',sigma )"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 9.3: Calculation_of_Polarization_vector_and_Displacement_vector_and_Energy_density.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"E = 1*10^5 // electric field strength inside the plates in V/m\n",
+"d = 6 // distance between the plates in mm\n",
+"k = 2.8 // dielectric constant of slab\n",
+"e_ = 8.85e-12 // electric permittivity of air in C^2/Nm^2\n",
+"// Sample Problem 3 on page no. 9.11\n",
+"printf('\n # PROBLEM 3 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' P = e_*(k-1)*E.\n\n ')\n",
+"P = e_*(k-1)*E\n",
+"D = e_*k*E\n",
+"energy_density = 1/2 * k*e_*E^2\n",
+"printf('Polarization vector is %e C/m^2. \n Displacement vector is %eC/m^2. \n Energy density is %f J/m^3.',P,D,energy_density )"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 9.4: EX9_4.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"D = 5e-4 // electric displacement vector in C/m^2\n",
+"P = 4e-4 // electric polarization vector in C/m^2\n",
+"v = 0.5 // volume of the slab in m^3\n",
+"e_ = 8.85e-12 // electric permittivity of air in C^2/Nm^2\n",
+"// Sample Problem 4 on page no. 9.12\n",
+"printf('\n # PROBLEM 4 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' D= e_*E.\n\n ')\n",
+"E= (D-P)/ e_\n",
+"k = D/(e_*E)\n",
+"p = P*v\n",
+"energy_density = 1/2 * k*e_*E^2\n",
+"printf('Value of relative permittivity is %d. \n Total dipole moment of the slab is %e C-m.',k,p )"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 9.5: Calculation_of_Induce_dipole_moment_of_each.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"E = 3e4 // external field in V/m\n",
+"k = 1.00074 // dielectric constant of gas at N.T.P.\n",
+"e_ = 8.85e-12 // electric permittivity of air in C^2/Nm^2\n",
+"// Sample Problem 5 on page no. 9.12\n",
+"printf('\n # PROBLEM 5 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' P=x*e_*E.\n\n ')\n",
+"x = k-1\n",
+"P = x*e_*E\n",
+"N = 6.023e23/22.4e-3\n",
+"p = P/N\n",
+"printf('Induce dipole moment of each is %e C-m',p)"
+   ]
+   }
+,
+{
+		   "cell_type": "markdown",
+		   "metadata": {},
+		   "source": [
+			"## Example 9.6: Calculation_of_Electric_susceptibility_at_0_degree_centigrade.sce"
+		   ]
+		  },
+  {
+"cell_type": "code",
+	   "execution_count": null,
+	   "metadata": {
+	    "collapsed": true
+	   },
+	   "outputs": [],
+"source": [
+"clc \n",
+"// Given that\n",
+"E = 3e4 // external field in V/m\n",
+"k = 1.000041 // dielectric constant of gas at 0 degree centigrate\n",
+"// Sample Problem 6 on page no. 9.1\n",
+"printf('\n # PROBLEM 6 # \n')\n",
+"printf(' Standard formula used \n')\n",
+"printf(' P=x*e_*E.\n\n ')\n",
+"x = k-1\n",
+"printf('Electric susceptibility at 0 degree centigrate is %e.',x)"
+   ]
+   }
+],
+"metadata": {
+		  "kernelspec": {
+		   "display_name": "Scilab",
+		   "language": "scilab",
+		   "name": "scilab"
+		  },
+		  "language_info": {
+		   "file_extension": ".sce",
+		   "help_links": [
+			{
+			 "text": "MetaKernel Magics",
+			 "url": "https://github.com/calysto/metakernel/blob/master/metakernel/magics/README.md"
+			}
+		   ],
+		   "mimetype": "text/x-octave",
+		   "name": "scilab",
+		   "version": "0.7.1"
+		  }
+		 },
+		 "nbformat": 4,
+		 "nbformat_minor": 0
+}